diff --git a/.tests/lib/BaseDatabaseTestCase.php b/.tests/lib/BaseDatabaseTestCase.php
index fcbb982..92bb68f 100644
--- a/.tests/lib/BaseDatabaseTestCase.php
+++ b/.tests/lib/BaseDatabaseTestCase.php
@@ -140,10 +140,10 @@ abstract class BaseDatabaseTestCase extends PHPUnit\DbUnit\TestCase {
    *
    * @param string $table Table name
    * @param array $rowsArr Array of rows
-   * @return int|null Last insert id if available, NULL otherwise
+   * @return int|null Last insert id if available, null otherwise
    */
   private function pdoInsert(string $table, array $rowsArr = []): ?int {
-    $ret = NULL;
+    $ret = null;
     if (!empty($rowsArr)) {
       $values = ':' . implode(', :', array_keys($rowsArr));
       $columns = implode(', ', array_keys($rowsArr));
@@ -161,7 +161,7 @@ abstract class BaseDatabaseTestCase extends PHPUnit\DbUnit\TestCase {
    * Execute raw insert query on database
    *
    * @param string $query Insert query
-   * @return int|null Last insert id if available, NULL otherwise
+   * @return int|null Last insert id if available, null otherwise
    */
   private function pdoInsertRaw(string $query): ?int {
     $ret = null;
diff --git a/.tests/tests/InternalAPITest.php b/.tests/tests/InternalAPITest.php
index e6971f1..7456583 100644
--- a/.tests/tests/InternalAPITest.php
+++ b/.tests/tests/InternalAPITest.php
@@ -37,19 +37,19 @@ class InternalAPITest extends UloggerAPITestCase {
 
     $position = $json[0];
     self::assertEquals(1, (int) $position->id, "Wrong position id");
-    self::assertEquals($this->testLat, (float) $position->latitude,"Wrong latitude");
-    self::assertEquals($this->testLon, (float) $position->longitude,"Wrong longitude");
-    self::assertEquals($this->testTimestamp, (int) $position->timestamp,"Wrong timestamp");
-    self::assertEquals($this->testAdminUser, (string) $position->username,"Wrong username");
-    self::assertEquals($this->testTrackName, (string) $position->trackname,"Wrong trackname");
+    self::assertEquals($this->testLat, (float) $position->latitude, "Wrong latitude");
+    self::assertEquals($this->testLon, (float) $position->longitude, "Wrong longitude");
+    self::assertEquals($this->testTimestamp, (int) $position->timestamp, "Wrong timestamp");
+    self::assertEquals($this->testAdminUser, (string) $position->username, "Wrong username");
+    self::assertEquals($this->testTrackName, (string) $position->trackname, "Wrong trackname");
 
     $position = $json[1];
-    self::assertEquals(2, (int) $position->id,"Wrong position id");
-    self::assertEquals($this->testLat, (float) $position->latitude,"Wrong latitude");
-    self::assertEquals($this->testLon, (float) $position->longitude,"Wrong longitude");
-    self::assertEquals($this->testTimestamp + 1, (int) $position->timestamp,"Wrong timestamp");
-    self::assertEquals($this->testAdminUser, (string) $position->username,"Wrong username");
-    self::assertEquals($this->testTrackName, (string) $position->trackname,"Wrong trackname");
+    self::assertEquals(2, (int) $position->id, "Wrong position id");
+    self::assertEquals($this->testLat, (float) $position->latitude, "Wrong latitude");
+    self::assertEquals($this->testLon, (float) $position->longitude, "Wrong longitude");
+    self::assertEquals($this->testTimestamp + 1, (int) $position->timestamp, "Wrong timestamp");
+    self::assertEquals($this->testAdminUser, (string) $position->username, "Wrong username");
+    self::assertEquals($this->testTrackName, (string) $position->trackname, "Wrong trackname");
   }
 
   /**
@@ -78,20 +78,20 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertCount(2, $json, "Wrong count of positions");
 
     $position = $json[0];
-    self::assertEquals(1, (int) $position->id,"Wrong position id");
-    self::assertEquals($this->testLat, (float) $position->latitude,"Wrong latitude");
-    self::assertEquals($this->testLon, (float) $position->longitude,"Wrong longitude");
-    self::assertEquals($this->testTimestamp, (int) $position->timestamp,"Wrong timestamp");
-    self::assertEquals($this->testUser, (string) $position->username,"Wrong username");
-    self::assertEquals($this->testTrackName, (string) $position->trackname,"Wrong trackname");
+    self::assertEquals(1, (int) $position->id, "Wrong position id");
+    self::assertEquals($this->testLat, (float) $position->latitude, "Wrong latitude");
+    self::assertEquals($this->testLon, (float) $position->longitude, "Wrong longitude");
+    self::assertEquals($this->testTimestamp, (int) $position->timestamp, "Wrong timestamp");
+    self::assertEquals($this->testUser, (string) $position->username, "Wrong username");
+    self::assertEquals($this->testTrackName, (string) $position->trackname, "Wrong trackname");
 
     $position = $json[1];
-    self::assertEquals(2, (int) $position->id,"Wrong position id");
-    self::assertEquals($this->testLat, (float) $position->latitude,"Wrong latitude");
-    self::assertEquals($this->testLon, (float) $position->longitude,"Wrong longitude");
-    self::assertEquals($this->testTimestamp + 1, (int) $position->timestamp,"Wrong timestamp");
-    self::assertEquals($this->testUser, (string) $position->username,"Wrong username");
-    self::assertEquals($this->testTrackName, (string) $position->trackname,"Wrong trackname");
+    self::assertEquals(2, (int) $position->id, "Wrong position id");
+    self::assertEquals($this->testLat, (float) $position->latitude, "Wrong latitude");
+    self::assertEquals($this->testLon, (float) $position->longitude, "Wrong longitude");
+    self::assertEquals($this->testTimestamp + 1, (int) $position->timestamp, "Wrong timestamp");
+    self::assertEquals($this->testUser, (string) $position->username, "Wrong username");
+    self::assertEquals($this->testTrackName, (string) $position->trackname, "Wrong trackname");
   }
 
   /**
@@ -148,20 +148,20 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertCount(2, $json, "Wrong count of positions");
 
     $position = $json[0];
-    self::assertEquals(1, (int) $position->id,"Wrong position id");
-    self::assertEquals($this->testLat, (float) $position->latitude,"Wrong latitude");
-    self::assertEquals($this->testLon, (float) $position->longitude,"Wrong longitude");
-    self::assertEquals($this->testTimestamp, (int) $position->timestamp,"Wrong timestamp");
-    self::assertEquals($this->testUser, (string) $position->username,"Wrong username");
-    self::assertEquals($this->testTrackName, (string) $position->trackname,"Wrong trackname");
+    self::assertEquals(1, (int) $position->id, "Wrong position id");
+    self::assertEquals($this->testLat, (float) $position->latitude, "Wrong latitude");
+    self::assertEquals($this->testLon, (float) $position->longitude, "Wrong longitude");
+    self::assertEquals($this->testTimestamp, (int) $position->timestamp, "Wrong timestamp");
+    self::assertEquals($this->testUser, (string) $position->username, "Wrong username");
+    self::assertEquals($this->testTrackName, (string) $position->trackname, "Wrong trackname");
 
     $position = $json[1];
-    self::assertEquals(2, (int) $position->id,"Wrong position id");
-    self::assertEquals($this->testLat, (float) $position->latitude,"Wrong latitude");
-    self::assertEquals($this->testLon, (float) $position->longitude,"Wrong longitude");
-    self::assertEquals($this->testTimestamp + 1, (int) $position->timestamp,"Wrong timestamp");
-    self::assertEquals($this->testUser, (string) $position->username,"Wrong username");
-    self::assertEquals($this->testTrackName, (string) $position->trackname,"Wrong trackname");
+    self::assertEquals(2, (int) $position->id, "Wrong position id");
+    self::assertEquals($this->testLat, (float) $position->latitude, "Wrong latitude");
+    self::assertEquals($this->testLon, (float) $position->longitude, "Wrong longitude");
+    self::assertEquals($this->testTimestamp + 1, (int) $position->timestamp, "Wrong timestamp");
+    self::assertEquals($this->testUser, (string) $position->username, "Wrong username");
+    self::assertEquals($this->testTrackName, (string) $position->trackname, "Wrong trackname");
   }
 
   /**
@@ -195,12 +195,12 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertCount(1, $json, "Wrong count of positions");
 
     $position = $json[0];
-    self::assertEquals(2, (int) $position->id,"Wrong position id");
-    self::assertEquals($this->testLat, (float) $position->latitude,"Wrong latitude");
-    self::assertEquals($this->testLon, (float) $position->longitude,"Wrong longitude");
-    self::assertEquals($this->testTimestamp + 3, (int) $position->timestamp,"Wrong timestamp");
-    self::assertEquals($this->testAdminUser, (string) $position->username,"Wrong username");
-    self::assertEquals($this->testTrackName, (string) $position->trackname,"Wrong trackname");
+    self::assertEquals(2, (int) $position->id, "Wrong position id");
+    self::assertEquals($this->testLat, (float) $position->latitude, "Wrong latitude");
+    self::assertEquals($this->testLon, (float) $position->longitude, "Wrong longitude");
+    self::assertEquals($this->testTimestamp + 3, (int) $position->timestamp, "Wrong timestamp");
+    self::assertEquals($this->testAdminUser, (string) $position->username, "Wrong username");
+    self::assertEquals($this->testTrackName, (string) $position->trackname, "Wrong trackname");
   }
 
   /**
@@ -235,20 +235,20 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertCount(2, $json, "Wrong count of positions");
 
     $position = $json[0];
-    self::assertEquals(2, (int) $position->id,"Wrong position id");
-    self::assertEquals($this->testLat, (float) $position->latitude,"Wrong latitude");
-    self::assertEquals($this->testLon, (float) $position->longitude,"Wrong longitude");
-    self::assertEquals($this->testTimestamp + 3, (int) $position->timestamp,"Wrong timestamp");
-    self::assertEquals($this->testAdminUser, (string) $position->username,"Wrong username");
-    self::assertEquals($this->testTrackName, (string) $position->trackname,"Wrong trackname");
+    self::assertEquals(2, (int) $position->id, "Wrong position id");
+    self::assertEquals($this->testLat, (float) $position->latitude, "Wrong latitude");
+    self::assertEquals($this->testLon, (float) $position->longitude, "Wrong longitude");
+    self::assertEquals($this->testTimestamp + 3, (int) $position->timestamp, "Wrong timestamp");
+    self::assertEquals($this->testAdminUser, (string) $position->username, "Wrong username");
+    self::assertEquals($this->testTrackName, (string) $position->trackname, "Wrong trackname");
 
     $position = $json[1];
-    self::assertEquals(3, (int) $position->id,"Wrong position id");
-    self::assertEquals($this->testLat, (float) $position->latitude,"Wrong latitude");
-    self::assertEquals($this->testLon, (float) $position->longitude,"Wrong longitude");
-    self::assertEquals($this->testTimestamp + 2, (int) $position->timestamp,"Wrong timestamp");
-    self::assertEquals($this->testUser, (string) $position->username,"Wrong username");
-    self::assertEquals($trackName, (string) $position->trackname,"Wrong trackname");
+    self::assertEquals(3, (int) $position->id, "Wrong position id");
+    self::assertEquals($this->testLat, (float) $position->latitude, "Wrong latitude");
+    self::assertEquals($this->testLon, (float) $position->longitude, "Wrong longitude");
+    self::assertEquals($this->testTimestamp + 2, (int) $position->timestamp, "Wrong timestamp");
+    self::assertEquals($this->testUser, (string) $position->username, "Wrong username");
+    self::assertEquals($trackName, (string) $position->trackname, "Wrong trackname");
   }
 
   /**
@@ -349,14 +349,14 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertCount(1, $json, "Wrong count of positions");
 
     $position = $json[0];
-    self::assertEquals($afterId + 1, (int) $position->id,"Wrong position id");
-    self::assertEquals($this->testLat + 1, (float) $position->latitude,"Wrong latitude");
-    self::assertEquals($this->testLon, (float) $position->longitude,"Wrong longitude");
-    self::assertEquals($this->testTimestamp + 1, (int) $position->timestamp,"Wrong timestamp");
-    self::assertEquals($this->testAdminUser, (string) $position->username,"Wrong username");
-    self::assertEquals($this->testTrackName, (string) $position->trackname,"Wrong trackname");
-    self::assertEquals(111195, (int) $position->meters,"Wrong distance delta");
-    self::assertEquals(1, (int) $position->seconds,"Wrong timestamp delta");
+    self::assertEquals($afterId + 1, (int) $position->id, "Wrong position id");
+    self::assertEquals($this->testLat + 1, (float) $position->latitude, "Wrong latitude");
+    self::assertEquals($this->testLon, (float) $position->longitude, "Wrong longitude");
+    self::assertEquals($this->testTimestamp + 1, (int) $position->timestamp, "Wrong timestamp");
+    self::assertEquals($this->testAdminUser, (string) $position->username, "Wrong username");
+    self::assertEquals($this->testTrackName, (string) $position->trackname, "Wrong trackname");
+    self::assertEquals(111195, (int) $position->meters, "Wrong distance delta");
+    self::assertEquals(1, (int) $position->seconds, "Wrong timestamp delta");
   }
 
 
@@ -387,12 +387,12 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertCount(2, $json, "Wrong count of tracks");
 
     $track = $json[0];
-    self::assertEquals($this->testTrackId2, (int) $track->id,"Wrong track id");
-    self::assertEquals($this->testTrackName . "2", (string) $track->name,"Wrong track name");
+    self::assertEquals($this->testTrackId2, (int) $track->id, "Wrong track id");
+    self::assertEquals($this->testTrackName . "2", (string) $track->name, "Wrong track name");
 
     $track = $json[1];
-    self::assertEquals($this->testTrackId, (int) $track->id,"Wrong track id");
-    self::assertEquals($this->testTrackName, (string) $track->name,"Wrong track name");
+    self::assertEquals($this->testTrackId, (int) $track->id, "Wrong track id");
+    self::assertEquals($this->testTrackName, (string) $track->name, "Wrong track name");
   }
 
   /**
@@ -420,12 +420,12 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertCount(2, $json, "Wrong count of tracks");
 
     $track = $json[0];
-    self::assertEquals($this->testTrackId2, (int) $track->id,"Wrong track id");
-    self::assertEquals($this->testTrackName . "2", (string) $track->name,"Wrong track name");
+    self::assertEquals($this->testTrackId2, (int) $track->id, "Wrong track id");
+    self::assertEquals($this->testTrackName . "2", (string) $track->name, "Wrong track name");
 
     $track = $json[1];
-    self::assertEquals($this->testTrackId, (int) $track->id,"Wrong track id");
-    self::assertEquals($this->testTrackName, (string) $track->name,"Wrong track name");
+    self::assertEquals($this->testTrackId, (int) $track->id, "Wrong track id");
+    self::assertEquals($this->testTrackName, (string) $track->name, "Wrong track name");
   }
 
   /**
@@ -626,8 +626,8 @@ class InternalAPITest extends UloggerAPITestCase {
 
     $json = json_decode($response->getBody());
     self::assertNotNull($json, "JSON object is null");
-    self::assertEquals(1, (int) $json->error,"Wrong error status");
-    self::assertEquals("Wrong old password", (string) $json->message,"Wrong error message");
+    self::assertEquals(1, (int) $json->error, "Wrong error status");
+    self::assertEquals("Wrong old password", (string) $json->message, "Wrong error message");
   }
 
   /**
@@ -871,8 +871,8 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertEquals(200, $response->getStatusCode(), "Unexpected status code");
     $json = json_decode($response->getBody());
     self::assertNotNull($json, "JSON object is null");
-    self::assertEquals(1, (int) $json->error,"Wrong error status");
-    self::assertEquals($lang["servererror"], (string) $json->message,"Wrong error message");
+    self::assertEquals(1, (int) $json->error, "Wrong error status");
+    self::assertEquals($lang["servererror"], (string) $json->message, "Wrong error message");
     self::assertEquals(2, $this->getConnection()->getRowCount("tracks"), "Wrong row count");
   }
 
@@ -899,8 +899,8 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertEquals(200, $response->getStatusCode(), "Unexpected status code");
     $json = json_decode($response->getBody());
     self::assertNotNull($json, "JSON object is null");
-    self::assertEquals(1, (int) $json->error,"Wrong error status");
-    self::assertEquals($lang["servererror"], (string) $json->message,"Wrong error message");
+    self::assertEquals(1, (int) $json->error, "Wrong error status");
+    self::assertEquals($lang["servererror"], (string) $json->message, "Wrong error message");
   }
 
   /**
@@ -918,7 +918,7 @@ class InternalAPITest extends UloggerAPITestCase {
     $json = json_decode($response->getBody());
     self::assertNotNull($json, "JSON object is null");
     self::assertEquals(1, (int) $json->error, "Wrong error status");
-    self::assertEquals($lang["servererror"], (string) $json->message,"Wrong error message");
+    self::assertEquals($lang["servererror"], (string) $json->message, "Wrong error message");
   }
 
 
@@ -938,8 +938,8 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertEquals(200, $response->getStatusCode(), "Unexpected status code");
     $json = json_decode($response->getBody());
     self::assertNotNull($json, "JSON object is null");
-    self::assertEquals(1, (int) $json->error,"Wrong error status");
-    self::assertEquals($lang["servererror"], (string) $json->message,"Wrong error message");
+    self::assertEquals(1, (int) $json->error, "Wrong error status");
+    self::assertEquals($lang["servererror"], (string) $json->message, "Wrong error message");
   }
 
   /**
@@ -959,8 +959,8 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertEquals(200, $response->getStatusCode(), "Unexpected status code");
     $json = json_decode($response->getBody());
     self::assertNotNull($json, "JSON object is null");
-    self::assertEquals(1, (int) $json->error,"Wrong error status");
-    self::assertEquals($lang["servererror"], (string) $json->message,"Wrong error message");
+    self::assertEquals(1, (int) $json->error, "Wrong error status");
+    self::assertEquals($lang["servererror"], (string) $json->message, "Wrong error message");
     self::assertEquals(2, $this->getConnection()->getRowCount("users"), "Wrong row count");
 
   }
@@ -981,8 +981,8 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertEquals(200, $response->getStatusCode(), "Unexpected status code");
     $json = json_decode($response->getBody());
     self::assertNotNull($json, "JSON object is null");
-    self::assertEquals(1, (int) $json->error,"Wrong error status");
-    self::assertEquals($lang["servererror"], (string) $json->message,"Wrong error message");
+    self::assertEquals(1, (int) $json->error, "Wrong error status");
+    self::assertEquals($lang["servererror"], (string) $json->message, "Wrong error message");
     self::assertEquals(1, $this->getConnection()->getRowCount("users"), "Wrong row count");
   }
 
@@ -1002,8 +1002,8 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertEquals(200, $response->getStatusCode(), "Unexpected status code");
     $json = json_decode($response->getBody());
     self::assertNotNull($json, "JSON object is null");
-    self::assertEquals(1, (int) $json->error,"Wrong error status");
-    self::assertEquals($lang["servererror"], (string) $json->message,"Wrong error message");
+    self::assertEquals(1, (int) $json->error, "Wrong error status");
+    self::assertEquals($lang["servererror"], (string) $json->message, "Wrong error message");
     self::assertEquals(1, $this->getConnection()->getRowCount("users"), "Wrong row count");
   }
 
@@ -1024,8 +1024,8 @@ class InternalAPITest extends UloggerAPITestCase {
     self::assertEquals(200, $response->getStatusCode(), "Unexpected status code");
     $json = json_decode($response->getBody());
     self::assertNotNull($json, "JSON object is null");
-    self::assertEquals(1, (int) $json->error,"Wrong error status");
-    self::assertEquals($lang["servererror"], (string) $json->message,"Wrong error message");
+    self::assertEquals(1, (int) $json->error, "Wrong error status");
+    self::assertEquals($lang["servererror"], (string) $json->message, "Wrong error message");
     self::assertEquals(2, $this->getConnection()->getRowCount("users"), "Wrong row count");
   }
 
@@ -1074,7 +1074,7 @@ class InternalAPITest extends UloggerAPITestCase {
     $json = json_decode($response->getBody());
     self::assertNotNull($json, "JSON object is null");
     self::assertEquals(1, (int) $json->error, "Wrong error status");
-    self::assertEquals($lang["userexists"], (string) $json->message,"Wrong error message");
+    self::assertEquals($lang["userexists"], (string) $json->message, "Wrong error message");
     self::assertEquals(2, $this->getConnection()->getRowCount("users"), "Wrong row count");
   }
 
diff --git a/.tests/tests/PositionTest.php b/.tests/tests/PositionTest.php
index c7f7a53..acac7d5 100644
--- a/.tests/tests/PositionTest.php
+++ b/.tests/tests/PositionTest.php
@@ -41,11 +41,11 @@ class PositionTest extends UloggerDatabaseTestCase {
     );
     $this->assertTableContains($expected, $actual, "Wrong actual table data");
 
-    $posId = uPosition::add($userId, $trackId, NULL, $this->testLat, $this->testLon);
+    $posId = uPosition::add($userId, $trackId, null, $this->testLat, $this->testLon);
     self::assertFalse($posId, "Adding position with null time stamp should fail");
-    $posId = uPosition::add($userId, $trackId, $this->testTimestamp, NULL, $this->testLon);
+    $posId = uPosition::add($userId, $trackId, $this->testTimestamp, null, $this->testLon);
     self::assertFalse($posId, "Adding position with null latitude should fail");
-    $posId = uPosition::add($userId, $trackId, $this->testTimestamp, $this->testLat, NULL);
+    $posId = uPosition::add($userId, $trackId, $this->testTimestamp, $this->testLat, null);
     self::assertFalse($posId, "Adding position with null longitude should fail");
 
     $posId = uPosition::add($userId, $trackId, "", $this->testLat, $this->testLon);
@@ -156,7 +156,7 @@ class PositionTest extends UloggerDatabaseTestCase {
     self::assertCount(2, $posArr, "Wrong row count");
     $posArr = uPosition::getAll($userId, $trackId);
     self::assertCount(1, $posArr, "Wrong row count");
-    $posArr = uPosition::getAll(NULL, $trackId);
+    $posArr = uPosition::getAll(null, $trackId);
     self::assertCount(1, $posArr, "Wrong row count");
     $posArr = uPosition::getAll($userId3);
     self::assertCount(0, $posArr, "Wrong row count");
diff --git a/.tests/tests/TrackTest.php b/.tests/tests/TrackTest.php
index 7dce897..700228c 100644
--- a/.tests/tests/TrackTest.php
+++ b/.tests/tests/TrackTest.php
@@ -72,11 +72,11 @@ class TrackTest extends UloggerDatabaseTestCase {
     );
     $this->assertTableContains($expected, $actual, "Wrong actual table data");
 
-    $posId = $track->addPosition($userId, NULL, $this->testLat, $this->testLon);
+    $posId = $track->addPosition($userId, null, $this->testLat, $this->testLon);
     self::assertFalse($posId, "Adding position with null time stamp should fail");
-    $posId = $track->addPosition($userId, $this->testTimestamp, NULL, $this->testLon);
+    $posId = $track->addPosition($userId, $this->testTimestamp, null, $this->testLon);
     self::assertFalse($posId, "Adding position with null latitude should fail");
-    $posId = $track->addPosition($userId, $this->testTimestamp, $this->testLat, NULL);
+    $posId = $track->addPosition($userId, $this->testTimestamp, $this->testLat, null);
     self::assertFalse($posId, "Adding position with null longitude should fail");
 
     $posId = $track->addPosition($userId, "", $this->testLat, $this->testLon);
@@ -113,7 +113,7 @@ class TrackTest extends UloggerDatabaseTestCase {
     uTrack::deleteAll($userId);
     self::assertEquals(1, $this->getConnection()->getRowCount('tracks'), "Wrong row count");
     self::assertEquals(1, $this->getConnection()->getRowCount('positions'), "Wrong row count");
-    self::assertFalse(uTrack::deleteAll(NULL), "User id should not be empty");
+    self::assertFalse(uTrack::deleteAll(null), "User id should not be empty");
   }
 
   public function testUpdate(): void {
diff --git a/.tests/tests/UserTest.php b/.tests/tests/UserTest.php
index 4bad7cd..0a0c1c7 100644
--- a/.tests/tests/UserTest.php
+++ b/.tests/tests/UserTest.php
@@ -75,7 +75,7 @@ class UserTest extends UloggerDatabaseTestCase {
   }
 
   public function testIsAdmin(): void {
-    $this->addTestUser($this->testUser, NULL, true);
+    $this->addTestUser($this->testUser, null, true);
     $user = new uUser($this->testUser);
     self::assertTrue($user->isAdmin, "User should be admin");
   }
diff --git a/css/src/main.css b/css/src/main.css
index 1a704bd..0c65bf3 100644
--- a/css/src/main.css
+++ b/css/src/main.css
@@ -85,7 +85,7 @@ select {
   width: 165px;
   padding-left: 10px;
   color: lightgray;
-  background-color: rgba(102, 102, 102, 0.9);
+  background-color: rgba(102, 102, 102, 90%);
 }
 
 #menu-button {
@@ -122,7 +122,7 @@ select {
 #menu.menu-hidden #menu-button {
   font-weight: normal;
   border-color: white;
-  background-color: rgba(0, 60, 136, 0.3);
+  background-color: rgba(0, 60, 136, 30%);
 }
 
 #menu.menu-hidden #menu-button a::after {
@@ -153,7 +153,7 @@ select {
   margin-top: 0.2em;
 }
 
-label[for=user] {
+label[for="user"] {
   display: block;
   padding-top: 1em;
 }
@@ -340,7 +340,7 @@ label[for=user] {
   width: 100%;
   height: 100%;
   background-color: black; /* fallback */
-  background-color: rgba(0, 0, 0, 0.4);
+  background-color: rgba(0, 0, 0, 40%);
 }
 
 #modal-header {
@@ -353,7 +353,7 @@ label[for=user] {
 
 #modal-header button {
   border: none;
-  background-color: rgba(0, 0, 0, 0);
+  background-color: rgba(0, 0, 0, 0%);
 }
 
 #modal-body {
@@ -363,13 +363,13 @@ label[for=user] {
   transform: translate(-50%, -50%) !important;
   font-size: 0.9em;
   min-width: 300px;
-  margin: 0 auto 15% auto;
+  margin: 0 auto 15%;
   padding: 1em;
   color: white;
   border: 1px solid #888;
   -webkit-border-radius: 10px;
   border-radius: 10px;
-  background-color: rgba(102, 102, 102, 0.9);
+  background-color: rgba(102, 102, 102, 90%);
   -moz-osx-font-smoothing: grayscale;
   -webkit-font-smoothing: antialiased;
 }
@@ -378,10 +378,10 @@ label[for=user] {
   padding-top: 1em;
 }
 
-#modal input[type=text],
-#modal input[type=color],
-#modal input[type=number],
-#modal input[type=password] {
+#modal input[type="text"],
+#modal input[type="color"],
+#modal input[type="number"],
+#modal input[type="password"] {
   display: inline-block;
   box-sizing: border-box;
   width: 100%;
@@ -395,7 +395,7 @@ label[for=user] {
 #modal.image {
   overflow: hidden;
   padding-top: 0;
-  background-color: rgba(45, 45, 45, 0.95);
+  background-color: rgba(45, 45, 45, 95%);
 }
 
 #modal.image #modal-body img {
@@ -466,11 +466,11 @@ button > * {
   text-decoration: underline;
 }
 
-#configForm label {
+#config-form label {
   display: block;
 }
 
-#configForm label b {
+#config-form label b {
   display: inline-block;
   text-align: right;
   width: 250px;
@@ -479,30 +479,30 @@ button > * {
   padding-top: 5px;
 }
 
-#configForm input[type=text],
-#configForm input[type=number],
-#configForm input[type=color],
-#configForm select {
+#config-form input[type="text"],
+#config-form input[type="number"],
+#config-form input[type="color"],
+#config-form select {
   width: 150px;
   margin: 3px 0;
   padding: 2px 4px;
   box-sizing: border-box;
 }
 
-#configForm input[type=checkbox] {
+#config-form input[type="checkbox"] {
   margin: 0;
 }
 
-#configForm select {
+#config-form select {
   padding: 2px 0;
 }
 
-#configForm input[type=color] {
+#config-form input[type="color"] {
   vertical-align: middle;
   padding: 0;
 }
 
-#configForm img {
+#config-form img {
   height: 13px;
   vertical-align: middle;
   margin: 0 5px;
@@ -531,7 +531,7 @@ button > * {
   padding: 6px 20px;
   border-radius: 5px;
   border-top: 1px solid #555;
-  box-shadow: 10px 10px 10px -8px rgba(0, 0, 0, 0.3);
+  box-shadow: 10px 10px 10px -8px rgba(0, 0, 0, 30%);
   z-index: 100000;
   opacity: 0;
   transition: all 1s;
@@ -596,7 +596,7 @@ button > * {
 }
 
 .alert.spinner > span::before, .alert.spinner > span::after {
-  content: '';
+  content: "";
   display: inline-block;
   position: absolute;
   top: 0;
@@ -661,8 +661,8 @@ button > * {
   border: 1px solid #ccc;
   border-radius: 10px;
   background-color: #666;
-  -webkit-filter: drop-shadow(0 1px 4px rgba(0, 0, 0, 0.2));
-  filter: drop-shadow(0 1px 4px rgba(0, 0, 0, 0.2));
+  -webkit-filter: drop-shadow(0 1px 4px rgba(0, 0, 0, 20%));
+  filter: drop-shadow(0 1px 4px rgba(0, 0, 0, 20%));
 }
 
 .ol-popup::after, .ol-popup::before {
@@ -695,7 +695,7 @@ button > * {
   right: -10px;
   width: 30px;
   height: 30px;
-  background-image: url(../../images/close.svg) !important;
+  background-image: url("../../images/close.svg") !important;
   background-repeat: no-repeat !important;
 }
 
@@ -710,11 +710,12 @@ button > * {
 }
 
 .gm-style .gm-style-iw-t::after {
-  background: linear-gradient(45deg, rgb(102, 102, 102) 50%, rgba(255, 255, 255, 0) 51%, rgba(255, 255, 255, 0) 100%) !important;
+  /* stylelint-disable-next-line max-line-length */
+  background: linear-gradient(45deg, rgb(102, 102, 102) 50%, rgba(255, 255, 255, 0%) 51%, rgba(255, 255, 255, 0%) 100%) !important;
 }
 
 .gm-style-iw button {
-  background-image: url(../../images/close.svg) !important;
+  background-image: url("../../images/close.svg") !important;
   background-repeat: no-repeat !important;
 }
 
@@ -744,11 +745,11 @@ button > * {
   color: #fff;
   border: none;
   border-radius: 2px;
-  background-color: rgba(0, 60, 136, 0.5);
+  background-color: rgba(0, 60, 136, 50%);
 }
 
 .ol-layerswitcher:hover {
-  background-color: rgba(0, 60, 136, 0.7);
+  background-color: rgba(0, 60, 136, 70%);
 }
 
 .ol-layerswitcher label {
diff --git a/helpers/auth.php b/helpers/auth.php
index 9908efa..6762b2f 100644
--- a/helpers/auth.php
+++ b/helpers/auth.php
@@ -17,185 +17,185 @@
  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
-  if (!defined('ROOT_DIR')) { define('ROOT_DIR', dirname(__DIR__)); }
-  require_once(ROOT_DIR . "/helpers/user.php");
-  require_once(ROOT_DIR . "/helpers/utils.php");
-  if (!defined('BASE_URL')) { define('BASE_URL', uUtils::getBaseUrl()); }
+if (!defined('ROOT_DIR')) { define('ROOT_DIR', dirname(__DIR__)); }
+require_once(ROOT_DIR . "/helpers/user.php");
+require_once(ROOT_DIR . "/helpers/utils.php");
+if (!defined('BASE_URL')) { define('BASE_URL', uUtils::getBaseUrl()); }
 
  /**
   * Authentication
   */
-  class uAuth {
+class uAuth {
 
-    /** @var bool Is user authenticated */
-    private $isAuthenticated = false;
-    /** @var null|uUser */
-    public $user;
+  /** @var bool Is user authenticated */
+  private $isAuthenticated = false;
+  /** @var null|uUser */
+  public $user;
 
-    public function __construct() {
-      $this->sessionStart();
+  public function __construct() {
+    $this->sessionStart();
 
-      $user = uUser::getFromSession();
-      if ($user->isValid) {
-        $this->setAuthenticated($user);
-      }
+    $user = uUser::getFromSession();
+    if ($user->isValid) {
+      $this->setAuthenticated($user);
     }
-
-    /**
-     * Update user instance stored in session
-     */
-    public function updateSession() {
-      if ($this->isAuthenticated()) {
-        $this->user->storeInSession();
-      }
-    }
-
-    /**
-     * Is user authenticated
-     *
-     * @return boolean True if authenticated, false otherwise
-     */
-    public function isAuthenticated() {
-      return $this->isAuthenticated;
-    }
-
-    /**
-     * Is authenticated user admin
-     *
-     * @return boolean True if admin, false otherwise
-     */
-    public function isAdmin() {
-      return ($this->isAuthenticated && $this->user->isAdmin);
-    }
-
-    /**
-     * Start php session
-     *
-     * @return void
-     */
-    private function sessionStart() {
-      session_name("ulogger");
-      session_start();
-    }
-
-    /**
-     * Terminate php session
-     *
-     * @return void
-     */
-    private function sessionEnd() {
-      $_SESSION = [];
-      if (ini_get("session.use_cookies") && isset($_COOKIE[session_name()])) {
-        $params = session_get_cookie_params();
-        setcookie(session_name(), '', time() - 42000,
-          $params["path"], $params["domain"],
-          $params["secure"], $params["httponly"]
-        );
-      }
-      session_destroy();
-    }
-
-    /**
-     * Clean session variables
-     *
-     * @return void
-     */
-    private function sessionCleanup() {
-      $_SESSION = [];
-    }
-
-    /**
-     * Mark as authenticated, set user
-     *
-     * @param uUser $user
-     * @return void
-     */
-    private function setAuthenticated($user) {
-      $this->isAuthenticated = true;
-      $this->user = $user;
-    }
-
-    /**
-     * Check valid pass for given login
-     *
-     * @param string $login
-     * @param string $pass
-     * @return boolean True if valid
-     */
-    public function checkLogin($login, $pass) {
-      if (!empty($login) && !empty($pass)) {
-        $user = new uUser($login);
-        if ($user->isValid && $user->validPassword($pass)) {
-          $this->setAuthenticated($user);
-          $this->sessionCleanup();
-          $user->storeInSession();
-          return true;
-        }
-      }
-      return false;
-    }
-
-    /**
-     * Log out with redirect
-     *
-     * @param string $path URL path (without leading slash)
-     * @return void
-     */
-    public function logOutWithRedirect($path = "") {
-      $this->sessionEnd();
-      $this->exitWithRedirect($path);
-    }
-
-    /**
-     * Send 401 headers
-     *
-     * @return void
-     */
-    public function sendUnauthorizedHeader() {
-      header('WWW-Authenticate: OAuth realm="users@ulogger"');
-      header('HTTP/1.1 401 Unauthorized', true, 401);
-    }
-
-    /**
-     * Send 401 headers and exit
-     *
-     * @return void
-     */
-    public function exitWithUnauthorized() {
-      $this->sendUnauthorizedHeader();
-      exit();
-    }
-
-    /**
-     * Redirect browser and exit
-     *
-     * @param string $path Redirect URL path (without leading slash)
-     * @return void
-     */
-    public function exitWithRedirect($path = "") {
-      $location = BASE_URL . $path;
-      header("Location: $location");
-      exit();
-    }
-
-    /**
-     * Check session user has RW access to resource owned by given user
-     *
-     * @param int $ownerId
-     * @return bool True if has access
-     */
-    public function hasReadWriteAccess($ownerId) {
-      return $this->isAuthenticated() && ($this->isAdmin() || $this->user->id === $ownerId);
-    }
-
-    /**
-     * Check session user has RO access to resource owned by given user
-     *
-     * @param int $ownerId
-     * @return bool True if has access
-     */
-    public function hasReadAccess($ownerId) {
-      return $this->hasReadWriteAccess($ownerId) || uConfig::getInstance()->publicTracks;
-    }
-
   }
+
+  /**
+   * Update user instance stored in session
+   */
+  public function updateSession() {
+    if ($this->isAuthenticated()) {
+      $this->user->storeInSession();
+    }
+  }
+
+  /**
+   * Is user authenticated
+   *
+   * @return boolean True if authenticated, false otherwise
+   */
+  public function isAuthenticated() {
+    return $this->isAuthenticated;
+  }
+
+  /**
+   * Is authenticated user admin
+   *
+   * @return boolean True if admin, false otherwise
+   */
+  public function isAdmin() {
+    return ($this->isAuthenticated && $this->user->isAdmin);
+  }
+
+  /**
+   * Start php session
+   *
+   * @return void
+   */
+  private function sessionStart() {
+    session_name("ulogger");
+    session_start();
+  }
+
+  /**
+   * Terminate php session
+   *
+   * @return void
+   */
+  private function sessionEnd() {
+    $_SESSION = [];
+    if (ini_get("session.use_cookies") && isset($_COOKIE[session_name()])) {
+      $params = session_get_cookie_params();
+      setcookie(session_name(), '', time() - 42000,
+        $params["path"], $params["domain"],
+        $params["secure"], $params["httponly"]
+      );
+    }
+    session_destroy();
+  }
+
+  /**
+   * Clean session variables
+   *
+   * @return void
+   */
+  private function sessionCleanup() {
+    $_SESSION = [];
+  }
+
+  /**
+   * Mark as authenticated, set user
+   *
+   * @param uUser $user
+   * @return void
+   */
+  private function setAuthenticated($user) {
+    $this->isAuthenticated = true;
+    $this->user = $user;
+  }
+
+  /**
+   * Check valid pass for given login
+   *
+   * @param string $login
+   * @param string $pass
+   * @return boolean True if valid
+   */
+  public function checkLogin($login, $pass) {
+    if (!empty($login) && !empty($pass)) {
+      $user = new uUser($login);
+      if ($user->isValid && $user->validPassword($pass)) {
+        $this->setAuthenticated($user);
+        $this->sessionCleanup();
+        $user->storeInSession();
+        return true;
+      }
+    }
+    return false;
+  }
+
+  /**
+   * Log out with redirect
+   *
+   * @param string $path URL path (without leading slash)
+   * @return void
+   */
+  public function logOutWithRedirect($path = "") {
+    $this->sessionEnd();
+    $this->exitWithRedirect($path);
+  }
+
+  /**
+   * Send 401 headers
+   *
+   * @return void
+   */
+  public function sendUnauthorizedHeader() {
+    header('WWW-Authenticate: OAuth realm="users@ulogger"');
+    header('HTTP/1.1 401 Unauthorized', true, 401);
+  }
+
+  /**
+   * Send 401 headers and exit
+   *
+   * @return void
+   */
+  public function exitWithUnauthorized() {
+    $this->sendUnauthorizedHeader();
+    exit();
+  }
+
+  /**
+   * Redirect browser and exit
+   *
+   * @param string $path Redirect URL path (without leading slash)
+   * @return void
+   */
+  public function exitWithRedirect($path = "") {
+    $location = BASE_URL . $path;
+    header("Location: $location");
+    exit();
+  }
+
+  /**
+   * Check session user has RW access to resource owned by given user
+   *
+   * @param int $ownerId
+   * @return bool True if has access
+   */
+  public function hasReadWriteAccess($ownerId) {
+    return $this->isAuthenticated() && ($this->isAdmin() || $this->user->id === $ownerId);
+  }
+
+  /**
+   * Check session user has RO access to resource owned by given user
+   *
+   * @param int $ownerId
+   * @return bool True if has access
+   */
+  public function hasReadAccess($ownerId) {
+    return $this->hasReadWriteAccess($ownerId) || uConfig::getInstance()->publicTracks;
+  }
+
+}
diff --git a/helpers/db.php b/helpers/db.php
index cc1bd63..085087d 100644
--- a/helpers/db.php
+++ b/helpers/db.php
@@ -19,302 +19,302 @@
 
 require_once(ROOT_DIR . "/helpers/utils.php");
 
- /**
-  * PDO wrapper
-  */
-  class uDb extends PDO {
-    /**
-     * Singleton instance
-     *
-     * @var uDb Object instance
-     */
-    protected static $instance;
+/**
+ * PDO wrapper
+ */
+class uDb extends PDO {
+  /**
+   * Singleton instance
+   *
+   * @var uDb Object instance
+   */
+  protected static $instance;
 
-    /**
-     * Table names
-     *
-     * @var array Array of names
-     */
-    protected static $tables;
+  /**
+   * Table names
+   *
+   * @var array Array of names
+   */
+  protected static $tables;
 
-    /**
-     * Database driver name
-     *
-     * @var string Driver
-     */
-    protected static $driver;
+  /**
+   * Database driver name
+   *
+   * @var string Driver
+   */
+  protected static $driver;
 
-    /**
-     * @var string Database DSN
-     */
-    private static $dbdsn = "";
-    /**
-     * @var string Database user
-     */
-    private static $dbuser = "";
-    /**
-     * @var string Database pass
-     */
-    private static $dbpass = "";
-    /**
-     * @var string Optional table names prefix, eg. "ulogger_"
-     */
-    private static $dbprefix = "";
+  /**
+   * @var string Database DSN
+   */
+  private static $dbdsn = "";
+  /**
+   * @var string Database user
+   */
+  private static $dbuser = "";
+  /**
+   * @var string Database pass
+   */
+  private static $dbpass = "";
+  /**
+   * @var string Optional table names prefix, eg. "ulogger_"
+   */
+  private static $dbprefix = "";
 
-   /**
-    * PDO constuctor
-    *
-    * @param string $dsn
-    * @param string $user
-    * @param string $pass
-    */
-    public function __construct($dsn, $user, $pass) {
-      try {
-        $options = [
-          PDO::ATTR_EMULATE_PREPARES   => false, // try to use native prepared statements
-          PDO::ATTR_ERRMODE            => PDO::ERRMODE_EXCEPTION, // throw exceptions
-          PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC, // return assoc array by default
-        ];
-        @parent::__construct($dsn, $user, $pass, $options);
-        self::$driver = $this->getAttribute(PDO::ATTR_DRIVER_NAME);
-        $this->setCharset("utf8");
-        $this->initTables();
-      } catch (PDOException $e) {
-        header("HTTP/1.1 503 Service Unavailable");
-        die("Database connection error (" . $e->getMessage() . ")");
-      }
-    }
-
-    /**
-     * Initialize table names based on config
-     */
-    private function initTables() {
-      self::$tables = [];
-      $prefix = preg_replace('/[^a-z0-9_]/i', '', self::$dbprefix);
-      self::$tables['positions'] = $prefix . "positions";
-      self::$tables['tracks'] = $prefix . "tracks";
-      self::$tables['users'] = $prefix . "users";
-      self::$tables['config'] = $prefix . "config";
-      self::$tables['ol_layers'] = $prefix . "ol_layers";
-    }
-
-   /**
-    * Returns singleton instance
-    *
-    * @return uDb Singleton instance
-    */
-    public static function getInstance() {
-      if (!self::$instance) {
-        self::getConfig();
-        self::$instance = new self(self::$dbdsn, self::$dbuser, self::$dbpass);
-      }
-      return self::$instance;
-    }
-
-    /**
-     * Read database setup from config file
-     * @noinspection IssetArgumentExistenceInspection
-     * @noinspection PhpIncludeInspection
-     */
-    private static function getConfig() {
-      $configFile = dirname(__DIR__) . "/config.php";
-      if (!file_exists($configFile)) {
-        header("HTTP/1.1 503 Service Unavailable");
-        die("Missing config.php file!");
-      }
-      include($configFile);
-      if (isset($dbdsn)) {
-        self::$dbdsn = self::normalizeDsn($dbdsn);
-      }
-      if (isset($dbuser)) {
-        self::$dbuser = $dbuser;
-      }
-      if (isset($dbpass)) {
-        self::$dbpass = $dbpass;
-      }
-      if (isset($dbprefix)) {
-        self::$dbprefix = $dbprefix;
-      }
-    }
-
-    /**
-    * Get full table name including prefix
-    *
-    * @param string $name Name
-    * @return string Full table name
-    */
-    public function table($name) {
-      return self::$tables[$name];
-    }
-
-    /**
-     * Returns function name for getting date-time column value as unix timestamp
-     * @param string $column
-     * @return string
-     */
-    public function unix_timestamp($column) {
-      switch (self::$driver) {
-        default:
-        case "mysql":
-          return "UNIX_TIMESTAMP($column)";
-          break;
-        case "pgsql":
-          return "EXTRACT(EPOCH FROM $column::TIMESTAMP WITH TIME ZONE)";
-          break;
-        case "sqlite":
-          return "STRFTIME('%s', $column)";
-          break;
-      }
-    }
-
-    /**
-     * Returns placeholder for LOB data types
-     * @return string
-     */
-    public function lobPlaceholder() {
-      switch (self::$driver) {
-        default:
-        case "mysql":
-        case "sqlite":
-        return "?";
-          break;
-        case "pgsql":
-          return "?::bytea";
-          break;
-      }
-    }
-
-    /**
-     * Returns construct for getting LOB as string
-     * @param string $column Column name
-     * @return string
-     */
-    public function from_lob($column) {
-      switch (self::$driver) {
-        default:
-        case "mysql":
-        case "sqlite":
-          return $column;
-          break;
-        case "pgsql":
-          return "encode($column, 'escape') AS $column";
-          break;
-      }
-    }
-
-    /**
-     * Returns function name for getting date-time column value as 'YYYY-MM-DD hh:mm:ss'
-     * @param string $column
-     * @return string
-     */
-    public function from_unixtime($column) {
-      switch (self::$driver) {
-        default:
-        case "mysql":
-          return "FROM_UNIXTIME($column)";
-          break;
-        case "pgsql":
-          return "TO_TIMESTAMP($column)";
-          break;
-        case "sqlite":
-          return "DATETIME($column, 'unixepoch')";
-          break;
-      }
-    }
-
-    /**
-     * Replace into
-     * Note: requires PostgreSQL >= 9.5
-     * @param string $table Table name (without prefix)
-     * @param string[] $columns Column names
-     * @param string[][] $values Values [ [ value1, value2 ], ... ]
-     * @param string $key Unique column
-     * @param string $update Updated column
-     * @return string
-     */
-    public function insertOrReplace($table, $columns, $values, $key, $update) {
-      $cols = implode(", ", $columns);
-      $rows = [];
-      foreach ($values as $row) {
-        $rows[] = "(" . implode(", ", $row) . ")";
-      }
-      $vals = implode(", ", $rows);
-      switch (self::$driver) {
-        default:
-        case "mysql":
-          return "INSERT INTO {$this->table($table)} ($cols)
-            VALUES $vals
-            ON DUPLICATE KEY UPDATE $update = VALUES($update)";
-          break;
-        case "pgsql":
-          return "INSERT INTO {$this->table($table)} ($cols)
-            VALUES $vals
-            ON CONFLICT ($key) DO UPDATE SET $update = EXCLUDED.$update";
-          break;
-        case "sqlite":
-          return "REPLACE INTO {$this->table($table)} ($cols)
-            VALUES $vals";
-          break;
-      }
-    }
-
-    /**
-     * Set character set
-     * @param string $charset
-     */
-    private function setCharset($charset) {
-      if (self::$driver === "pgsql" || self::$driver === "mysql") {
-        $this->exec("SET NAMES '$charset'");
-      }
-    }
-
-    /**
-     * Extract database name from DSN
-     * @param string $dsn
-     * @return string Empty string if not found
-     */
-    public static function getDbName($dsn) {
-      $name = "";
-      if (strpos($dsn, ":") !== false) {
-        list($scheme, $dsnWithoutScheme) = explode(":", $dsn, 2);
-        switch ($scheme) {
-          case "sqlite":
-          case "sqlite2":
-          case "sqlite3":
-            $pattern = "/(.+)/";
-            break;
-          case "pgsql":
-            $pattern = "/dbname=([^; ]+)/";
-            break;
-          default:
-            $pattern = "/dbname=([^;]+)/";
-            break;
-        }
-        $result = preg_match($pattern, $dsnWithoutScheme, $matches);
-        if ($result === 1) {
-          $name = $matches[1];
-        }
-      }
-      return $name;
-    }
-
-    /**
-     * Normalize DSN.
-     * Make sure sqlite DSN file path is absolute
-     * @param $dsn string DSN
-     * @return string Normalized DSN
-     */
-    public static function normalizeDsn($dsn) {
-      if (stripos($dsn, "sqlite") !== 0) {
-        return $dsn;
-      }
-      $arr = explode(":", $dsn, 2);
-      if (count($arr) < 2 || empty($arr[1]) || uUtils::isAbsolutePath($arr[1])) {
-        return $dsn;
-      }
-      $scheme = $arr[0];
-      $path = dirname(__DIR__) . DIRECTORY_SEPARATOR . $arr[1];
-      return $scheme . ":" . realpath(dirname($path)) . DIRECTORY_SEPARATOR . basename(($path));
+  /**
+   * PDO constuctor
+   *
+   * @param string $dsn
+   * @param string $user
+   * @param string $pass
+   */
+  public function __construct($dsn, $user, $pass) {
+    try {
+      $options = [
+        PDO::ATTR_EMULATE_PREPARES   => false, // try to use native prepared statements
+        PDO::ATTR_ERRMODE            => PDO::ERRMODE_EXCEPTION, // throw exceptions
+        PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC, // return assoc array by default
+      ];
+      @parent::__construct($dsn, $user, $pass, $options);
+      self::$driver = $this->getAttribute(PDO::ATTR_DRIVER_NAME);
+      $this->setCharset("utf8");
+      $this->initTables();
+    } catch (PDOException $e) {
+      header("HTTP/1.1 503 Service Unavailable");
+      die("Database connection error (" . $e->getMessage() . ")");
     }
   }
+
+  /**
+   * Initialize table names based on config
+   */
+  private function initTables() {
+    self::$tables = [];
+    $prefix = preg_replace('/[^a-z0-9_]/i', '', self::$dbprefix);
+    self::$tables['positions'] = $prefix . "positions";
+    self::$tables['tracks'] = $prefix . "tracks";
+    self::$tables['users'] = $prefix . "users";
+    self::$tables['config'] = $prefix . "config";
+    self::$tables['ol_layers'] = $prefix . "ol_layers";
+  }
+
+  /**
+   * Returns singleton instance
+   *
+   * @return uDb Singleton instance
+   */
+  public static function getInstance() {
+    if (!self::$instance) {
+      self::getConfig();
+      self::$instance = new self(self::$dbdsn, self::$dbuser, self::$dbpass);
+    }
+    return self::$instance;
+  }
+
+  /**
+   * Read database setup from config file
+   * @noinspection IssetArgumentExistenceInspection
+   * @noinspection PhpIncludeInspection
+   */
+  private static function getConfig() {
+    $configFile = dirname(__DIR__) . "/config.php";
+    if (!file_exists($configFile)) {
+      header("HTTP/1.1 503 Service Unavailable");
+      die("Missing config.php file!");
+    }
+    include($configFile);
+    if (isset($dbdsn)) {
+      self::$dbdsn = self::normalizeDsn($dbdsn);
+    }
+    if (isset($dbuser)) {
+      self::$dbuser = $dbuser;
+    }
+    if (isset($dbpass)) {
+      self::$dbpass = $dbpass;
+    }
+    if (isset($dbprefix)) {
+      self::$dbprefix = $dbprefix;
+    }
+  }
+
+  /**
+   * Get full table name including prefix
+   *
+   * @param string $name Name
+   * @return string Full table name
+   */
+  public function table($name) {
+    return self::$tables[$name];
+  }
+
+  /**
+   * Returns function name for getting date-time column value as unix timestamp
+   * @param string $column
+   * @return string
+   */
+  public function unix_timestamp($column) {
+    switch (self::$driver) {
+      default:
+      case "mysql":
+        return "UNIX_TIMESTAMP($column)";
+        break;
+      case "pgsql":
+        return "EXTRACT(EPOCH FROM $column::TIMESTAMP WITH TIME ZONE)";
+        break;
+      case "sqlite":
+        return "STRFTIME('%s', $column)";
+        break;
+    }
+  }
+
+  /**
+   * Returns placeholder for LOB data types
+   * @return string
+   */
+  public function lobPlaceholder() {
+    switch (self::$driver) {
+      default:
+      case "mysql":
+      case "sqlite":
+      return "?";
+        break;
+      case "pgsql":
+        return "?::bytea";
+        break;
+    }
+  }
+
+  /**
+   * Returns construct for getting LOB as string
+   * @param string $column Column name
+   * @return string
+   */
+  public function from_lob($column) {
+    switch (self::$driver) {
+      default:
+      case "mysql":
+      case "sqlite":
+        return $column;
+        break;
+      case "pgsql":
+        return "encode($column, 'escape') AS $column";
+        break;
+    }
+  }
+
+  /**
+   * Returns function name for getting date-time column value as 'YYYY-MM-DD hh:mm:ss'
+   * @param string $column
+   * @return string
+   */
+  public function from_unixtime($column) {
+    switch (self::$driver) {
+      default:
+      case "mysql":
+        return "FROM_UNIXTIME($column)";
+        break;
+      case "pgsql":
+        return "TO_TIMESTAMP($column)";
+        break;
+      case "sqlite":
+        return "DATETIME($column, 'unixepoch')";
+        break;
+    }
+  }
+
+  /**
+   * Replace into
+   * Note: requires PostgreSQL >= 9.5
+   * @param string $table Table name (without prefix)
+   * @param string[] $columns Column names
+   * @param string[][] $values Values [ [ value1, value2 ], ... ]
+   * @param string $key Unique column
+   * @param string $update Updated column
+   * @return string
+   */
+  public function insertOrReplace($table, $columns, $values, $key, $update) {
+    $cols = implode(", ", $columns);
+    $rows = [];
+    foreach ($values as $row) {
+      $rows[] = "(" . implode(", ", $row) . ")";
+    }
+    $vals = implode(", ", $rows);
+    switch (self::$driver) {
+      default:
+      case "mysql":
+        return "INSERT INTO {$this->table($table)} ($cols)
+          VALUES $vals
+          ON DUPLICATE KEY UPDATE $update = VALUES($update)";
+        break;
+      case "pgsql":
+        return "INSERT INTO {$this->table($table)} ($cols)
+          VALUES $vals
+          ON CONFLICT ($key) DO UPDATE SET $update = EXCLUDED.$update";
+        break;
+      case "sqlite":
+        return "REPLACE INTO {$this->table($table)} ($cols)
+          VALUES $vals";
+        break;
+    }
+  }
+
+  /**
+   * Set character set
+   * @param string $charset
+   */
+  private function setCharset($charset) {
+    if (self::$driver === "pgsql" || self::$driver === "mysql") {
+      $this->exec("SET NAMES '$charset'");
+    }
+  }
+
+  /**
+   * Extract database name from DSN
+   * @param string $dsn
+   * @return string Empty string if not found
+   */
+  public static function getDbName($dsn) {
+    $name = "";
+    if ($dsn && strpos($dsn, ":") !== false) {
+      list($scheme, $dsnWithoutScheme) = explode(":", $dsn, 2);
+      switch ($scheme) {
+        case "sqlite":
+        case "sqlite2":
+        case "sqlite3":
+          $pattern = "/(.+)/";
+          break;
+        case "pgsql":
+          $pattern = "/dbname=([^; ]+)/";
+          break;
+        default:
+          $pattern = "/dbname=([^;]+)/";
+          break;
+      }
+      $result = preg_match($pattern, $dsnWithoutScheme, $matches);
+      if ($result === 1) {
+        $name = $matches[1];
+      }
+    }
+    return $name;
+  }
+
+  /**
+   * Normalize DSN.
+   * Make sure sqlite DSN file path is absolute
+   * @param string $dsn DSN
+   * @return string Normalized DSN
+   */
+  public static function normalizeDsn($dsn) {
+    if (stripos($dsn, "sqlite") !== 0) {
+      return $dsn;
+    }
+    $arr = explode(":", $dsn, 2);
+    if (count($arr) < 2 || empty($arr[1]) || uUtils::isAbsolutePath($arr[1])) {
+      return $dsn;
+    }
+    $scheme = $arr[0];
+    $path = dirname(__DIR__) . DIRECTORY_SEPARATOR . $arr[1];
+    return $scheme . ":" . realpath(dirname($path)) . DIRECTORY_SEPARATOR . basename(($path));
+  }
+}
 ?>
diff --git a/helpers/lang.php b/helpers/lang.php
index d352397..b6e14c1 100644
--- a/helpers/lang.php
+++ b/helpers/lang.php
@@ -17,100 +17,100 @@
  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
-  require_once(ROOT_DIR . "/helpers/config.php");
+require_once(ROOT_DIR . "/helpers/config.php");
+
+/**
+ * Localization
+ */
+class uLang {
 
   /**
-  * Localization
-  */
-  class uLang {
+   * Available languages
+   *
+   * @var array
+   */
+  private static $languages = [
+    "ca" => "Català",
+    "cs" => "Čeština",
+    "de" => "Deutsch",
+    "el" => "Ελληνικά",
+    "en" => "English",
+    "es" => "Español",
+    "eu" => "Euskera",
+    "fr" => "Français",
+    "it" => "Italiano",
+    "pl" => "Polski",
+    "ru" => "Русский",
+    "sk" => "Slovenčina"
+  ];
 
-    /**
-     * Available languages
-     *
-     * @var array
-     */
-    private static $languages = [
-      "ca" => "Català",
-      "cs" => "Čeština",
-      "de" => "Deutsch",
-      "el" => "Ελληνικά",
-      "en" => "English",
-      "es" => "Español",
-      "eu" => "Euskera",
-      "fr" => "Français",
-      "it" => "Italiano",
-      "pl" => "Polski",
-      "ru" => "Русский",
-      "sk" => "Slovenčina"
-    ];
+  /**
+   * Application strings
+   * Array of key => translation pairs
+   *
+   * @var array
+   */
+  private $strings;
+  /**
+   * Setup script strings
+   * Array of key => translation pairs
+   *
+   * @var array
+   */
+  private $setupStrings;
 
-    /**
-     * Application strings
-     * Array of key => translation pairs
-     *
-     * @var array
-     */
-    private $strings;
-    /**
-     * Setup script strings
-     * Array of key => translation pairs
-     *
-     * @var array
-     */
-    private $setupStrings;
+  /**
+   * Constructor
+   *
+   * @param uConfig $config Config
+   */
+  public function __construct($config) {
+    $language = $config->lang;
+    $lang = [];
+    $langSetup = [];
+    // always load en base
+    require(ROOT_DIR . "/lang/en.php");
 
-    /**
-     * Constructor
-     *
-     * @param uConfig $config Config
-     */
-    public function __construct($config) {
-      $language = $config->lang;
-      $lang = [];
-      $langSetup = [];
-      // always load en base
-      require(ROOT_DIR . "/lang/en.php");
-
-      // override with translated strings if needed
-      // missing strings will be displayed in English
-      if ($language !== "en" && array_key_exists($language, self::$languages)) {
-        require(ROOT_DIR . "/lang/$language.php");
-      }
-
-      $this->strings = $lang;
-      $this->setupStrings = $langSetup;
-    }
-
-    /**
-     * Get supported languages array
-     * Language code => Native language name
-     *
-     * @return array
-     */
-    public static function getLanguages() {
-      return self::$languages;
-    }
-
-    /**
-     * Get translated strings array
-     * Key => translation string
-     *
-     * @return array
-     */
-    public function getStrings() {
-      return $this->strings;
-    }
-
-    /**
-     * Get translated strings array for setup script
-     * Key => translation string
-     *
-     * @return array
-     */
-    public function getSetupStrings() {
-      return $this->setupStrings;
+    // override with translated strings if needed
+    // missing strings will be displayed in English
+    if ($language !== "en" && array_key_exists($language, self::$languages)) {
+      require(ROOT_DIR . "/lang/$language.php");
     }
 
+    $this->strings = $lang;
+    $this->setupStrings = $langSetup;
   }
 
- ?>
+  /**
+   * Get supported languages array
+   * Language code => Native language name
+   *
+   * @return array
+   */
+  public static function getLanguages() {
+    return self::$languages;
+  }
+
+  /**
+   * Get translated strings array
+   * Key => translation string
+   *
+   * @return array
+   */
+  public function getStrings() {
+    return $this->strings;
+  }
+
+  /**
+   * Get translated strings array for setup script
+   * Key => translation string
+   *
+   * @return array
+   */
+  public function getSetupStrings() {
+    return $this->setupStrings;
+  }
+
+}
+
+?>
diff --git a/helpers/position.php b/helpers/position.php
index 96764ec..86f8ce9 100644
--- a/helpers/position.php
+++ b/helpers/position.php
@@ -21,485 +21,485 @@ require_once(ROOT_DIR . "/helpers/db.php");
 require_once(ROOT_DIR . "/helpers/track.php");
 require_once(ROOT_DIR . "/helpers/upload.php");
 
- /**
-  * Positions handling
-  */
-  class uPosition {
-    /** @param int Position id */
-    public $id;
-    /** @param int Unix time stamp */
-    public $timestamp;
-    /** @param int User id */
-    public $userId;
-    /** @param String User login */
-    public $userLogin;
-    /** @param int Track id */
-    public $trackId;
-    /** @param String Track name */
-    public $trackName;
-    /** @param double Latitude */
-    public $latitude;
-    /** @param double Longitude */
-    public $longitude;
-    /** @param double Altitude */
-    public $altitude;
-    /** @param double Speed */
-    public $speed;
-    /** @param double Bearing */
-    public $bearing;
-    /** @param int Accuracy */
-    public $accuracy;
-    /** @param String Provider */
-    public $provider;
-    /** @param String Comment */
-    public $comment;
-    /** @param String Image path */
-    public $image;
+/**
+ * Positions handling
+ */
+class uPosition {
+  /** @param int Position id */
+  public $id;
+  /** @param int Unix time stamp */
+  public $timestamp;
+  /** @param int User id */
+  public $userId;
+  /** @param String User login */
+  public $userLogin;
+  /** @param int Track id */
+  public $trackId;
+  /** @param String Track name */
+  public $trackName;
+  /** @param double Latitude */
+  public $latitude;
+  /** @param double Longitude */
+  public $longitude;
+  /** @param double Altitude */
+  public $altitude;
+  /** @param double Speed */
+  public $speed;
+  /** @param double Bearing */
+  public $bearing;
+  /** @param int Accuracy */
+  public $accuracy;
+  /** @param String Provider */
+  public $provider;
+  /** @param String Comment */
+  public $comment;
+  /** @param String Image path */
+  public $image;
 
-    public $isValid = false;
+  public $isValid = false;
 
-   /**
-    * Constructor
-    * @param integer $positionId Position id
-    */
-    public function __construct($positionId = NULL) {
+  /**
+   * Constructor
+   * @param integer $positionId Position id
+   */
+  public function __construct($positionId = null) {
 
-      if (!empty($positionId)) {
-        $query = "SELECT p.id, " . self::db()->unix_timestamp('p.time') . " AS tstamp, p.user_id, p.track_id,
-                  p.latitude, p.longitude, p.altitude, p.speed, p.bearing, p.accuracy, p.provider,
-                  p.comment, p.image, u.login, t.name
-                  FROM " . self::db()->table('positions') . " p
-                  LEFT JOIN " . self::db()->table('users') . " u ON (p.user_id = u.id)
-                  LEFT JOIN " . self::db()->table('tracks') . " t ON (p.track_id = t.id)
-                  WHERE p.id = ? LIMIT 1";
-        $params = [ $positionId ];
-        try {
-          $this->loadWithQuery($query, $params);
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-      }
-    }
-
-    /**
-     * Get db instance
-     *
-     * @return uDb instance
-     */
-    private static function db() {
-      return uDb::getInstance();
-    }
-
-    /**
-     * Has image
-     *
-     * @return bool True if has image
-     */
-    public function hasImage() {
-      return !empty($this->image);
-    }
-
-   /**
-    * Add position
-    *
-    * @param int $userId
-    * @param int $trackId
-    * @param int $timestamp Unix time stamp
-    * @param double $lat
-    * @param double $lon
-    * @param double $altitude Optional
-    * @param double $speed Optional
-    * @param double $bearing Optional
-    * @param int $accuracy Optional
-    * @param string $provider Optional
-    * @param string $comment Optional
-    * @param int $image Optional
-    * @return int|bool New position id in database, false on error
-    */
-    public static function add($userId, $trackId, $timestamp, $lat, $lon,
-                               $altitude = NULL, $speed = NULL, $bearing = NULL, $accuracy = NULL,
-                               $provider = NULL, $comment = NULL, $image = NULL) {
-      $positionId = false;
-      if (is_numeric($lat) && is_numeric($lon) && is_numeric($timestamp) && is_numeric($userId) && is_numeric($trackId)) {
-        $track = new uTrack($trackId);
-        if ($track->isValid && $track->userId === $userId) {
-          try {
-            $table = self::db()->table('positions');
-            $query = "INSERT INTO $table
-                      (user_id, track_id,
-                      time, latitude, longitude, altitude, speed, bearing, accuracy, provider, comment, image)
-                      VALUES (?, ?, " . self::db()->from_unixtime('?') . ", ?, ?, ?, ?, ?, ?, ?, ?, ?)";
-            $stmt = self::db()->prepare($query);
-            $params = [ $userId, $trackId,
-                    $timestamp, $lat, $lon, $altitude, $speed, $bearing, $accuracy, $provider, $comment, $image ];
-            $stmt->execute($params);
-            $positionId = (int) self::db()->lastInsertId("${table}_id_seq");
-          } catch (PDOException $e) {
-            // TODO: handle error
-            syslog(LOG_ERR, $e->getMessage());
-          }
-        }
-      }
-      return $positionId;
-    }
-
-    /**
-     * Save position to database
-     *
-     * @return bool True if success, false otherwise
-     */
-    public function update() {
-      $ret = false;
-      if ($this->isValid) {
-        try {
-          $query = "UPDATE " . self::db()->table('positions') . " SET 
-                    time = " . self::db()->from_unixtime('?') . ", user_id = ?, track_id = ?, latitude = ?, longitude = ?, altitude = ?, 
-                    speed = ?, bearing = ?, accuracy = ?, provider = ?, comment = ?, image = ? WHERE id = ?";
-          $stmt = self::db()->prepare($query);
-          $params = [
-            $this->timestamp,
-            $this->userId,
-            $this->trackId,
-            $this->latitude,
-            $this->longitude,
-            $this->altitude,
-            $this->speed,
-            $this->bearing,
-            $this->accuracy,
-            $this->provider,
-            $this->comment,
-            $this->image,
-            $this->id
-          ];
-          $stmt->execute($params);
-          $ret = true;
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-      }
-      return $ret;
-    }
-
-    /**
-     * Delete positions
-     *
-     * @return bool True if success, false otherwise
-     */
-    public function delete() {
-      $ret = false;
-      if ($this->isValid) {
-        try {
-          $query = "DELETE FROM " . self::db()->table('positions') . " WHERE id = ?";
-          $stmt = self::db()->prepare($query);
-          $stmt->execute([ $this->id ]);
-          $this->removeImage();
-          $ret = true;
-          $this->id = NULL;
-          $this->isValid = false;
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-      }
-      return $ret;
-    }
-
-   /**
-    * Delete all user's positions, optionally limit to given track
-    *
-    * @param int $userId User id
-    * @param int $trackId Optional track id
-    * @return bool True if success, false otherwise
-    */
-    public static function deleteAll($userId, $trackId = NULL) {
-      $ret = false;
-      if (!empty($userId)) {
-        $args = [];
-        $where = "WHERE user_id = ?";
-        $args[] = $userId;
-        if (!empty($trackId)) {
-          $where .= " AND track_id = ?";
-          $args[] = $trackId;
-        }
-        self::removeImages($userId, $trackId);
-        try {
-          $query = "DELETE FROM " . self::db()->table('positions') . " $where";
-          $stmt = self::db()->prepare($query);
-          $stmt->execute($args);
-          $ret = true;
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-      }
-      return $ret;
-    }
-
-   /**
-    * Get last position data from database
-    * (for given user if specified)
-    *
-    * @param int $userId Optional user id
-    * @return uPosition Position
-    */
-    public static function getLast($userId = NULL) {
-      if (!empty($userId)) {
-        $where = "WHERE p.user_id = ?";
-        $params = [ $userId ];
-      } else {
-        $where = "";
-        $params = NULL;
-      }
+    if (!empty($positionId)) {
       $query = "SELECT p.id, " . self::db()->unix_timestamp('p.time') . " AS tstamp, p.user_id, p.track_id,
                 p.latitude, p.longitude, p.altitude, p.speed, p.bearing, p.accuracy, p.provider,
                 p.comment, p.image, u.login, t.name
                 FROM " . self::db()->table('positions') . " p
                 LEFT JOIN " . self::db()->table('users') . " u ON (p.user_id = u.id)
                 LEFT JOIN " . self::db()->table('tracks') . " t ON (p.track_id = t.id)
-                $where
-                ORDER BY p.time DESC, p.id DESC LIMIT 1";
-      $position = new uPosition();
+                WHERE p.id = ? LIMIT 1";
+      $params = [ $positionId ];
       try {
-        $position->loadWithQuery($query, $params);
+        $this->loadWithQuery($query, $params);
       } catch (PDOException $e) {
         // TODO: handle exception
         syslog(LOG_ERR, $e->getMessage());
       }
-      return $position;
-    }
-
-   /**
-    * Get last positions for all users
-    *
-    * @return array|bool Array of uPosition positions, false on error
-    */
-    public static function getLastAllUsers() {
-      $query = "SELECT p.id, " . self::db()->unix_timestamp('p.time') . " AS tstamp, p.user_id, p.track_id,
-                p.latitude, p.longitude, p.altitude, p.speed, p.bearing, p.accuracy, p.provider,
-                p.comment, p.image, u.login, t.name
-                FROM " . self::db()->table('positions') . " p
-                LEFT JOIN " . self::db()->table('users') . " u ON (p.user_id = u.id)
-                LEFT JOIN " . self::db()->table('tracks') . " t ON (p.track_id = t.id)
-                WHERE  p.id = (
-                  SELECT p2.id FROM " . self::db()->table('positions') . " p2
-                  WHERE p2.user_id = p.user_id
-                  ORDER BY p2.time DESC, p2.id DESC
-                  LIMIT 1
-                )";
-      $positionsArr = [];
-      try {
-        $result = self::db()->query($query);
-        while ($row = $result->fetch()) {
-          $positionsArr[] = self::rowToObject($row);
-        }
-      } catch (PDOException $e) {
-        // TODO: handle exception
-        syslog(LOG_ERR, $e->getMessage());
-        $positionsArr = false;
-      }
-      return $positionsArr;
-    }
-
-    /**
-     * Get array of all positions
-     *
-     * @param int $userId Optional limit to given user id
-     * @param int $trackId Optional limit to given track id
-     * @param int $afterId Optional limit to positions with id greater then given id
-     * @param array $rules Optional rules
-     * @return uPosition[]|bool Array of uPosition positions, false on error
-     */
-    public static function getAll($userId = NULL, $trackId = NULL, $afterId = NULL, $rules = []) {
-      if (!empty($userId)) {
-        $rules[] = "p.user_id = " . self::db()->quote($userId);
-      }
-      if (!empty($trackId)) {
-        $rules[] = "p.track_id = " . self::db()->quote($trackId);
-      }
-      if (!empty($afterId)) {
-        $rules[] = "p.id > " . self::db()->quote($afterId);
-      }
-      if (!empty($rules)) {
-        $where = "WHERE " . implode(" AND ", $rules);
-      } else {
-        $where = "";
-      }
-      $query = "SELECT p.id, " . self::db()->unix_timestamp('p.time') . " AS tstamp, p.user_id, p.track_id,
-                p.latitude, p.longitude, p.altitude, p.speed, p.bearing, p.accuracy, p.provider,
-                p.comment, p.image, u.login, t.name
-                FROM " . self::db()->table('positions') . " p
-                LEFT JOIN " . self::db()->table('users') . " u ON (p.user_id = u.id)
-                LEFT JOIN " . self::db()->table('tracks') . " t ON (p.track_id = t.id)
-                $where
-                ORDER BY p.time, p.id";
-      $positionsArr = [];
-      try {
-        $result = self::db()->query($query);
-        while ($row = $result->fetch()) {
-          $positionsArr[] = self::rowToObject($row);
-        }
-      } catch (PDOException $e) {
-        // TODO: handle exception
-        syslog(LOG_ERR, $e->getMessage());
-        $positionsArr = false;
-      }
-      return $positionsArr;
-    }
-
-    /**
-     * Get array of all positions with image
-     *
-     * @param int $userId Optional limit to given user id
-     * @param int $trackId Optional limit to given track id
-     * @param int $afterId Optional limit to positions with id greater then given id
-     * @param array $rules Optional rules
-     * @return uPosition[]|bool Array of uPosition positions, false on error
-     */
-    public static function getAllWithImage($userId = NULL, $trackId = NULL, $afterId = NULL, $rules = []) {
-      $rules[] = "p.image IS NOT NULL";
-      return self::getAll($userId, $trackId, $afterId, $rules);
-    }
-
-    /**
-     * Delete all user's uploads, optionally limit to given track
-     *
-     * @param int $userId User id
-     * @param int $trackId Optional track id
-     * @return bool True if success, false otherwise
-     */
-    public static function removeImages($userId, $trackId = NULL) {
-      if (($positions = self::getAllWithImage($userId, $trackId)) !== false) {
-        foreach ($positions as $position) {
-          try {
-            $position->removeImage();
-          } catch (PDOException $e) {
-            // TODO: handle exception
-            syslog(LOG_ERR, $e->getMessage());
-            return false;
-          }
-        }
-      }
-      return true;
-    }
-
-    /**
-     * Add uploaded image
-     * @param array $imageMeta File metadata array
-     */
-    public function setImage($imageMeta) {
-      if (!empty($imageMeta)) {
-        if ($this->hasImage()) {
-          $this->removeImage();
-        }
-        $this->image = uUpload::add($imageMeta, $this->trackId);
-        $query = "UPDATE " . self::db()->table('positions') . "
-              SET image = ? WHERE id = ?";
-        $stmt = self::db()->prepare($query);
-        $stmt->execute([ $this->image, $this->id ]);
-      }
-    }
-
-    /**
-     * Delete image
-     */
-    public function removeImage() {
-      if ($this->hasImage()) {
-        $query = "UPDATE " . self::db()->table('positions') . "
-              SET image = NULL WHERE id = ?";
-        $stmt = self::db()->prepare($query);
-        $stmt->execute([ $this->id ]);
-        // ignore unlink errors
-        uUpload::delete($this->image);
-        $this->image = null;
-      }
-    }
-
-   /**
-    * Calculate distance to target point using haversine formula
-    *
-    * @param uPosition $target Target position
-    * @return int Distance in meters
-    */
-    public function distanceTo($target) {
-      $lat1 = deg2rad($this->latitude);
-      $lon1 = deg2rad($this->longitude);
-      $lat2 = deg2rad($target->latitude);
-      $lon2 = deg2rad($target->longitude);
-      $latD = $lat2 - $lat1;
-      $lonD = $lon2 - $lon1;
-      $bearing = 2 * asin(sqrt((sin($latD / 2) ** 2) + cos($lat1) * cos($lat2) * (sin($lonD / 2) ** 2)));
-      return $bearing * 6371000;
-    }
-
-   /**
-    * Calculate time elapsed since target point
-    *
-    * @param uPosition $target Target position
-    * @return int Number of seconds
-    */
-    public function secondsTo($target) {
-      return $this->timestamp - $target->timestamp;
-    }
-
-   /**
-    * Convert database row to uPosition
-    *
-    * @param array $row Row
-    * @return uPosition Position
-    */
-    private static function rowToObject($row) {
-      $position = new uPosition();
-      $position->id = (int) $row['id'];
-      $position->timestamp = (int) $row['tstamp'];
-      $position->userId = (int) $row['user_id'];
-      $position->userLogin = $row['login'];
-      $position->trackId = (int) $row['track_id'];
-      $position->trackName = $row['name'];
-      $position->latitude = (double) $row['latitude'];
-      $position->longitude = (double) $row['longitude'];
-      $position->altitude = (double) $row['altitude'];
-      $position->speed = (double) $row['speed'];
-      $position->bearing = (double) $row['bearing'];
-      $position->accuracy = (int) $row['accuracy'];
-      $position->provider = $row['provider'];
-      $position->comment = $row['comment'];
-      $position->image = $row['image'];
-      $position->isValid = true;
-      return $position;
-    }
-
-   /**
-    * Fill class properties with database query result
-    *
-    * @param string $query Query
-    * @param array|null $params Optional array of bind parameters
-    * @throws PDOException
-    */
-    private function loadWithQuery($query, $params = NULL) {
-      $stmt = self::db()->prepare($query);
-      $stmt->execute($params);
-
-      $stmt->bindColumn('id', $this->id, PDO::PARAM_INT);
-      $stmt->bindColumn('tstamp', $this->timestamp, PDO::PARAM_INT);
-      $stmt->bindColumn('user_id', $this->userId, PDO::PARAM_INT);
-      $stmt->bindColumn('track_id', $this->trackId, PDO::PARAM_INT);
-      $stmt->bindColumn('latitude', $this->latitude);
-      $stmt->bindColumn('longitude', $this->longitude);
-      $stmt->bindColumn('altitude', $this->altitude);
-      $stmt->bindColumn('speed', $this->speed);
-      $stmt->bindColumn('bearing', $this->bearing);
-      $stmt->bindColumn('accuracy', $this->accuracy, PDO::PARAM_INT);
-      $stmt->bindColumn('provider', $this->provider);
-      $stmt->bindColumn('comment', $this->comment);
-      $stmt->bindColumn('image', $this->image);
-      $stmt->bindColumn('login', $this->userLogin);
-      $stmt->bindColumn('name', $this->trackName);
-      if ($stmt->fetch(PDO::FETCH_BOUND)) {
-        $this->isValid = true;
-      }
     }
   }
 
+  /**
+   * Get db instance
+   *
+   * @return uDb instance
+   */
+  private static function db() {
+    return uDb::getInstance();
+  }
+
+  /**
+   * Has image
+   *
+   * @return bool True if has image
+   */
+  public function hasImage() {
+    return !empty($this->image);
+  }
+
+  /**
+   * Add position
+   *
+   * @param int $userId
+   * @param int $trackId
+   * @param int $timestamp Unix time stamp
+   * @param double $lat
+   * @param double $lon
+   * @param double $altitude Optional
+   * @param double $speed Optional
+   * @param double $bearing Optional
+   * @param int $accuracy Optional
+   * @param string $provider Optional
+   * @param string $comment Optional
+   * @param int $image Optional
+   * @return int|bool New position id in database, false on error
+   */
+  public static function add($userId, $trackId, $timestamp, $lat, $lon,
+                              $altitude = null, $speed = null, $bearing = null, $accuracy = null,
+                              $provider = null, $comment = null, $image = null) {
+    $positionId = false;
+    if (is_numeric($lat) && is_numeric($lon) && is_numeric($timestamp) && is_numeric($userId) && is_numeric($trackId)) {
+      $track = new uTrack($trackId);
+      if ($track->isValid && $track->userId === $userId) {
+        try {
+          $table = self::db()->table('positions');
+          $query = "INSERT INTO $table
+                    (user_id, track_id,
+                    time, latitude, longitude, altitude, speed, bearing, accuracy, provider, comment, image)
+                    VALUES (?, ?, " . self::db()->from_unixtime('?') . ", ?, ?, ?, ?, ?, ?, ?, ?, ?)";
+          $stmt = self::db()->prepare($query);
+          $params = [ $userId, $trackId,
+                  $timestamp, $lat, $lon, $altitude, $speed, $bearing, $accuracy, $provider, $comment, $image ];
+          $stmt->execute($params);
+          $positionId = (int) self::db()->lastInsertId("${table}_id_seq");
+        } catch (PDOException $e) {
+          // TODO: handle error
+          syslog(LOG_ERR, $e->getMessage());
+        }
+      }
+    }
+    return $positionId;
+  }
+
+  /**
+   * Save position to database
+   *
+   * @return bool True if success, false otherwise
+   */
+  public function update() {
+    $ret = false;
+    if ($this->isValid) {
+      try {
+        $query = "UPDATE " . self::db()->table('positions') . " SET 
+                  time = " . self::db()->from_unixtime('?') . ", user_id = ?, track_id = ?, latitude = ?, longitude = ?, altitude = ?, 
+                  speed = ?, bearing = ?, accuracy = ?, provider = ?, comment = ?, image = ? WHERE id = ?";
+        $stmt = self::db()->prepare($query);
+        $params = [
+          $this->timestamp,
+          $this->userId,
+          $this->trackId,
+          $this->latitude,
+          $this->longitude,
+          $this->altitude,
+          $this->speed,
+          $this->bearing,
+          $this->accuracy,
+          $this->provider,
+          $this->comment,
+          $this->image,
+          $this->id
+        ];
+        $stmt->execute($params);
+        $ret = true;
+      } catch (PDOException $e) {
+        // TODO: handle exception
+        syslog(LOG_ERR, $e->getMessage());
+      }
+    }
+    return $ret;
+  }
+
+  /**
+   * Delete positions
+   *
+   * @return bool True if success, false otherwise
+   */
+  public function delete() {
+    $ret = false;
+    if ($this->isValid) {
+      try {
+        $query = "DELETE FROM " . self::db()->table('positions') . " WHERE id = ?";
+        $stmt = self::db()->prepare($query);
+        $stmt->execute([ $this->id ]);
+        $this->removeImage();
+        $ret = true;
+        $this->id = null;
+        $this->isValid = false;
+      } catch (PDOException $e) {
+        // TODO: handle exception
+        syslog(LOG_ERR, $e->getMessage());
+      }
+    }
+    return $ret;
+  }
+
+  /**
+   * Delete all user's positions, optionally limit to given track
+   *
+   * @param int $userId User id
+   * @param int $trackId Optional track id
+   * @return bool True if success, false otherwise
+   */
+  public static function deleteAll($userId, $trackId = null) {
+    $ret = false;
+    if (!empty($userId)) {
+      $args = [];
+      $where = "WHERE user_id = ?";
+      $args[] = $userId;
+      if (!empty($trackId)) {
+        $where .= " AND track_id = ?";
+        $args[] = $trackId;
+      }
+      self::removeImages($userId, $trackId);
+      try {
+        $query = "DELETE FROM " . self::db()->table('positions') . " $where";
+        $stmt = self::db()->prepare($query);
+        $stmt->execute($args);
+        $ret = true;
+      } catch (PDOException $e) {
+        // TODO: handle exception
+        syslog(LOG_ERR, $e->getMessage());
+      }
+    }
+    return $ret;
+  }
+
+  /**
+   * Get last position data from database
+   * (for given user if specified)
+   *
+   * @param int $userId Optional user id
+   * @return uPosition Position
+   */
+  public static function getLast($userId = null) {
+    if (!empty($userId)) {
+      $where = "WHERE p.user_id = ?";
+      $params = [ $userId ];
+    } else {
+      $where = "";
+      $params = null;
+    }
+    $query = "SELECT p.id, " . self::db()->unix_timestamp('p.time') . " AS tstamp, p.user_id, p.track_id,
+              p.latitude, p.longitude, p.altitude, p.speed, p.bearing, p.accuracy, p.provider,
+              p.comment, p.image, u.login, t.name
+              FROM " . self::db()->table('positions') . " p
+              LEFT JOIN " . self::db()->table('users') . " u ON (p.user_id = u.id)
+              LEFT JOIN " . self::db()->table('tracks') . " t ON (p.track_id = t.id)
+              $where
+              ORDER BY p.time DESC, p.id DESC LIMIT 1";
+    $position = new uPosition();
+    try {
+      $position->loadWithQuery($query, $params);
+    } catch (PDOException $e) {
+      // TODO: handle exception
+      syslog(LOG_ERR, $e->getMessage());
+    }
+    return $position;
+  }
+
+  /**
+   * Get last positions for all users
+   *
+   * @return array|bool Array of uPosition positions, false on error
+   */
+  public static function getLastAllUsers() {
+    $query = "SELECT p.id, " . self::db()->unix_timestamp('p.time') . " AS tstamp, p.user_id, p.track_id,
+              p.latitude, p.longitude, p.altitude, p.speed, p.bearing, p.accuracy, p.provider,
+              p.comment, p.image, u.login, t.name
+              FROM " . self::db()->table('positions') . " p
+              LEFT JOIN " . self::db()->table('users') . " u ON (p.user_id = u.id)
+              LEFT JOIN " . self::db()->table('tracks') . " t ON (p.track_id = t.id)
+              WHERE  p.id = (
+                SELECT p2.id FROM " . self::db()->table('positions') . " p2
+                WHERE p2.user_id = p.user_id
+                ORDER BY p2.time DESC, p2.id DESC
+                LIMIT 1
+              )";
+    $positionsArr = [];
+    try {
+      $result = self::db()->query($query);
+      while ($row = $result->fetch()) {
+        $positionsArr[] = self::rowToObject($row);
+      }
+    } catch (PDOException $e) {
+      // TODO: handle exception
+      syslog(LOG_ERR, $e->getMessage());
+      $positionsArr = false;
+    }
+    return $positionsArr;
+  }
+
+  /**
+   * Get array of all positions
+   *
+   * @param int $userId Optional limit to given user id
+   * @param int $trackId Optional limit to given track id
+   * @param int $afterId Optional limit to positions with id greater then given id
+   * @param array $rules Optional rules
+   * @return uPosition[]|bool Array of uPosition positions, false on error
+   */
+  public static function getAll($userId = null, $trackId = null, $afterId = null, $rules = []) {
+    if (!empty($userId)) {
+      $rules[] = "p.user_id = " . self::db()->quote($userId);
+    }
+    if (!empty($trackId)) {
+      $rules[] = "p.track_id = " . self::db()->quote($trackId);
+    }
+    if (!empty($afterId)) {
+      $rules[] = "p.id > " . self::db()->quote($afterId);
+    }
+    if (!empty($rules)) {
+      $where = "WHERE " . implode(" AND ", $rules);
+    } else {
+      $where = "";
+    }
+    $query = "SELECT p.id, " . self::db()->unix_timestamp('p.time') . " AS tstamp, p.user_id, p.track_id,
+              p.latitude, p.longitude, p.altitude, p.speed, p.bearing, p.accuracy, p.provider,
+              p.comment, p.image, u.login, t.name
+              FROM " . self::db()->table('positions') . " p
+              LEFT JOIN " . self::db()->table('users') . " u ON (p.user_id = u.id)
+              LEFT JOIN " . self::db()->table('tracks') . " t ON (p.track_id = t.id)
+              $where
+              ORDER BY p.time, p.id";
+    $positionsArr = [];
+    try {
+      $result = self::db()->query($query);
+      while ($row = $result->fetch()) {
+        $positionsArr[] = self::rowToObject($row);
+      }
+    } catch (PDOException $e) {
+      // TODO: handle exception
+      syslog(LOG_ERR, $e->getMessage());
+      $positionsArr = false;
+    }
+    return $positionsArr;
+  }
+
+  /**
+   * Get array of all positions with image
+   *
+   * @param int $userId Optional limit to given user id
+   * @param int $trackId Optional limit to given track id
+   * @param int $afterId Optional limit to positions with id greater then given id
+   * @param array $rules Optional rules
+   * @return uPosition[]|bool Array of uPosition positions, false on error
+   */
+  public static function getAllWithImage($userId = null, $trackId = null, $afterId = null, $rules = []) {
+    $rules[] = "p.image IS NOT NULL";
+    return self::getAll($userId, $trackId, $afterId, $rules);
+  }
+
+  /**
+   * Delete all user's uploads, optionally limit to given track
+   *
+   * @param int $userId User id
+   * @param int $trackId Optional track id
+   * @return bool True if success, false otherwise
+   */
+  public static function removeImages($userId, $trackId = null) {
+    if (($positions = self::getAllWithImage($userId, $trackId)) !== false) {
+      foreach ($positions as $position) {
+        try {
+          $position->removeImage();
+        } catch (PDOException $e) {
+          // TODO: handle exception
+          syslog(LOG_ERR, $e->getMessage());
+          return false;
+        }
+      }
+    }
+    return true;
+  }
+
+  /**
+   * Add uploaded image
+   * @param array $imageMeta File metadata array
+   */
+  public function setImage($imageMeta) {
+    if (!empty($imageMeta)) {
+      if ($this->hasImage()) {
+        $this->removeImage();
+      }
+      $this->image = uUpload::add($imageMeta, $this->trackId);
+      $query = "UPDATE " . self::db()->table('positions') . "
+            SET image = ? WHERE id = ?";
+      $stmt = self::db()->prepare($query);
+      $stmt->execute([ $this->image, $this->id ]);
+    }
+  }
+
+  /**
+   * Delete image
+   */
+  public function removeImage() {
+    if ($this->hasImage()) {
+      $query = "UPDATE " . self::db()->table('positions') . "
+            SET image = NULL WHERE id = ?";
+      $stmt = self::db()->prepare($query);
+      $stmt->execute([ $this->id ]);
+      // ignore unlink errors
+      uUpload::delete($this->image);
+      $this->image = null;
+    }
+  }
+
+  /**
+   * Calculate distance to target point using haversine formula
+   *
+   * @param uPosition $target Target position
+   * @return int Distance in meters
+   */
+  public function distanceTo($target) {
+    $lat1 = deg2rad($this->latitude);
+    $lon1 = deg2rad($this->longitude);
+    $lat2 = deg2rad($target->latitude);
+    $lon2 = deg2rad($target->longitude);
+    $latD = $lat2 - $lat1;
+    $lonD = $lon2 - $lon1;
+    $bearing = 2 * asin(sqrt((sin($latD / 2) ** 2) + cos($lat1) * cos($lat2) * (sin($lonD / 2) ** 2)));
+    return $bearing * 6371000;
+  }
+
+  /**
+   * Calculate time elapsed since target point
+   *
+   * @param uPosition $target Target position
+   * @return int Number of seconds
+   */
+  public function secondsTo($target) {
+    return $this->timestamp - $target->timestamp;
+  }
+
+  /**
+   * Convert database row to uPosition
+   *
+   * @param array $row Row
+   * @return uPosition Position
+   */
+  private static function rowToObject($row) {
+    $position = new uPosition();
+    $position->id = (int) $row['id'];
+    $position->timestamp = (int) $row['tstamp'];
+    $position->userId = (int) $row['user_id'];
+    $position->userLogin = $row['login'];
+    $position->trackId = (int) $row['track_id'];
+    $position->trackName = $row['name'];
+    $position->latitude = (double) $row['latitude'];
+    $position->longitude = (double) $row['longitude'];
+    $position->altitude = (double) $row['altitude'];
+    $position->speed = (double) $row['speed'];
+    $position->bearing = (double) $row['bearing'];
+    $position->accuracy = (int) $row['accuracy'];
+    $position->provider = $row['provider'];
+    $position->comment = $row['comment'];
+    $position->image = $row['image'];
+    $position->isValid = true;
+    return $position;
+  }
+
+  /**
+   * Fill class properties with database query result
+   *
+   * @param string $query Query
+   * @param array|null $params Optional array of bind parameters
+   * @throws PDOException
+   */
+  private function loadWithQuery($query, $params = null) {
+    $stmt = self::db()->prepare($query);
+    $stmt->execute($params);
+
+    $stmt->bindColumn('id', $this->id, PDO::PARAM_INT);
+    $stmt->bindColumn('tstamp', $this->timestamp, PDO::PARAM_INT);
+    $stmt->bindColumn('user_id', $this->userId, PDO::PARAM_INT);
+    $stmt->bindColumn('track_id', $this->trackId, PDO::PARAM_INT);
+    $stmt->bindColumn('latitude', $this->latitude);
+    $stmt->bindColumn('longitude', $this->longitude);
+    $stmt->bindColumn('altitude', $this->altitude);
+    $stmt->bindColumn('speed', $this->speed);
+    $stmt->bindColumn('bearing', $this->bearing);
+    $stmt->bindColumn('accuracy', $this->accuracy, PDO::PARAM_INT);
+    $stmt->bindColumn('provider', $this->provider);
+    $stmt->bindColumn('comment', $this->comment);
+    $stmt->bindColumn('image', $this->image);
+    $stmt->bindColumn('login', $this->userLogin);
+    $stmt->bindColumn('name', $this->trackName);
+    if ($stmt->fetch(PDO::FETCH_BOUND)) {
+      $this->isValid = true;
+    }
+  }
+}
+
 ?>
diff --git a/helpers/track.php b/helpers/track.php
index 6010d41..6fd8a07 100644
--- a/helpers/track.php
+++ b/helpers/track.php
@@ -20,227 +20,227 @@
   require_once(ROOT_DIR . "/helpers/db.php");
   require_once(ROOT_DIR . "/helpers/position.php");
 
- /**
-  * Track handling
-  */
-  class uTrack {
-    public $id;
-    public $userId;
-    public $name;
-    public $comment;
+/**
+ * Track handling
+ */
+class uTrack {
+  public $id;
+  public $userId;
+  public $name;
+  public $comment;
 
-    public $isValid = false;
+  public $isValid = false;
 
-   /**
-    * Constructor
-    *
-    * @param int $trackId Track id
-    */
-    public function __construct($trackId = NULL) {
+  /**
+   * Constructor
+   *
+   * @param int $trackId Track id
+   */
+  public function __construct($trackId = null) {
 
-      if (!empty($trackId)) {
-        try {
-          $query = "SELECT id, user_id, name, comment FROM " . self::db()->table('tracks') . " WHERE id = ? LIMIT 1";
-          $stmt = self::db()->prepare($query);
-          $stmt->execute([$trackId]);
-          $stmt->bindColumn('id', $this->id, PDO::PARAM_INT);
-          $stmt->bindColumn('user_id', $this->userId, PDO::PARAM_INT);
-          $stmt->bindColumn('name', $this->name);
-          $stmt->bindColumn('comment', $this->comment);
-          if ($stmt->fetch(PDO::FETCH_BOUND)) {
-            $this->isValid = true;
-          }
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-
-      }
-    }
-
-    /**
-     * Get db instance
-     *
-     * @return uDb instance
-     */
-    private static function db() {
-      return uDb::getInstance();
-    }
-
-   /**
-    * Add new track
-    *
-    * @param string $userId User id
-    * @param string $name Name
-    * @param string $comment Optional comment
-    * @return int|bool New track id, false on error
-    */
-    public static function add($userId, $name, $comment = NULL) {
-      $trackId = false;
-      if (!empty($userId) && !empty($name)) {
-        try {
-          $table = self::db()->table('tracks');
-          $query = "INSERT INTO $table (user_id, name, comment) VALUES (?, ?, ?)";
-          $stmt = self::db()->prepare($query);
-          $params = [ $userId, $name, $comment ];
-          $stmt->execute($params);
-          $trackId = (int) self::db()->lastInsertId("${table}_id_seq");
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-      }
-      return $trackId;
-    }
-
-    /**
-     * Add new position to track
-     *
-     * @param int $userId
-     * @param int $timestamp Unix time stamp
-     * @param double $lat
-     * @param double $lon
-     * @param double $altitude Optional
-     * @param double $speed Optional
-     * @param double $bearing Optional
-     * @param int $accuracy Optional
-     * @param string $provider Optional
-     * @param string $comment Optional
-     * @param int $imageId Optional
-     * @return int|bool New position id in database, false on error
-     */
-    public function addPosition($userId, $timestamp, $lat, $lon,
-                                $altitude = NULL, $speed = NULL, $bearing = NULL, $accuracy = NULL,
-                                $provider = NULL, $comment = NULL, $imageId = NULL) {
-      return uPosition::add($userId, $this->id, $timestamp, $lat, $lon,
-                                   $altitude, $speed, $bearing, $accuracy, $provider, $comment, $imageId);
-    }
-
-   /**
-    * Delete track with all positions
-    *
-    * @return bool True if success, false otherwise
-    */
-    public function delete() {
-      $ret = false;
-      if ($this->isValid) {
-        // delete positions
-        if (uPosition::deleteAll($this->userId, $this->id) === false) {
-          return false;
-        }
-        // delete track metadata
-        try {
-          $query = "DELETE FROM " . self::db()->table('tracks') . " WHERE id = ?";
-          $stmt = self::db()->prepare($query);
-          $stmt->execute([ $this->id ]);
-          $ret = true;
-          $this->id = NULL;
-          $this->userId = NULL;
-          $this->name = NULL;
-          $this->comment = NULL;
-          $this->isValid = false;
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-      }
-      return $ret;
-    }
-
-   /**
-    * Update track
-    *
-    * @param string|null $name New name (not empty string) or NULL if not changed
-    * @param string|null $comment New comment or NULL if not changed (to remove content use empty string: "")
-    * @return bool True if success, false otherwise
-    */
-    public function update($name = NULL, $comment = NULL) {
-      $ret = false;
-      if (empty($name)) { $name = $this->name; }
-      if (is_null($comment)) { $comment = $this->comment; }
-      if ($comment === "") { $comment = NULL; }
-      if ($this->isValid) {
-        try {
-          $query = "UPDATE " . self::db()->table('tracks') . " SET name = ?, comment = ? WHERE id = ?";
-          $stmt = self::db()->prepare($query);
-          $params = [ $name, $comment, $this->id ];
-          $stmt->execute($params);
-          $ret = true;
-          $this->name = $name;
-          $this->comment = $comment;
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-      }
-      return $ret;
-    }
-
-   /**
-    * Delete all user's tracks
-    *
-    * @param string $userId User id
-    * @return bool True if success, false otherwise
-    */
-    public static function deleteAll($userId) {
-      $ret = false;
-      if (!empty($userId) && uPosition::deleteAll($userId) === true) {
-        // remove all tracks
-        try {
-          $query = "DELETE FROM " . self::db()->table('tracks') . " WHERE user_id = ?";
-          $stmt = self::db()->prepare($query);
-          $stmt->execute([ $userId ]);
-          $ret = true;
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-      }
-      return $ret;
-    }
-
-   /**
-    * Get all tracks
-    *
-    * @param int $userId Optional limit to user id
-    * @return array|bool Array of uTrack tracks, false on error
-    */
-    public static function getAll($userId = NULL) {
-      if (!empty($userId)) {
-        $where = "WHERE user_id=" . self::db()->quote($userId);
-      } else {
-        $where = "";
-      }
-      $query = "SELECT id, user_id, name, comment FROM " . self::db()->table('tracks') . " $where ORDER BY id DESC";
+    if (!empty($trackId)) {
       try {
-        $result = self::db()->query($query);
-        $trackArr = [];
-        while ($row = $result->fetch()) {
-          $trackArr[] = self::rowToObject($row);
+        $query = "SELECT id, user_id, name, comment FROM " . self::db()->table('tracks') . " WHERE id = ? LIMIT 1";
+        $stmt = self::db()->prepare($query);
+        $stmt->execute([$trackId]);
+        $stmt->bindColumn('id', $this->id, PDO::PARAM_INT);
+        $stmt->bindColumn('user_id', $this->userId, PDO::PARAM_INT);
+        $stmt->bindColumn('name', $this->name);
+        $stmt->bindColumn('comment', $this->comment);
+        if ($stmt->fetch(PDO::FETCH_BOUND)) {
+          $this->isValid = true;
         }
       } catch (PDOException $e) {
         // TODO: handle exception
         syslog(LOG_ERR, $e->getMessage());
-        $trackArr = false;
       }
-      return $trackArr;
-    }
 
-   /**
-    * Convert database row to uTrack
-    *
-    * @param array $row Row
-    * @return uTrack Track
-    */
-    private static function rowToObject($row) {
-      $track = new uTrack();
-      $track->id = (int) $row['id'];
-      $track->userId = (int) $row['user_id'];
-      $track->name = $row['name'];
-      $track->comment = $row['comment'];
-      $track->isValid = true;
-      return $track;
     }
   }
 
+  /**
+   * Get db instance
+   *
+   * @return uDb instance
+   */
+  private static function db() {
+    return uDb::getInstance();
+  }
+
+  /**
+   * Add new track
+   *
+   * @param string $userId User id
+   * @param string $name Name
+   * @param string $comment Optional comment
+   * @return int|bool New track id, false on error
+   */
+  public static function add($userId, $name, $comment = null) {
+    $trackId = false;
+    if (!empty($userId) && !empty($name)) {
+      try {
+        $table = self::db()->table('tracks');
+        $query = "INSERT INTO $table (user_id, name, comment) VALUES (?, ?, ?)";
+        $stmt = self::db()->prepare($query);
+        $params = [ $userId, $name, $comment ];
+        $stmt->execute($params);
+        $trackId = (int) self::db()->lastInsertId("${table}_id_seq");
+      } catch (PDOException $e) {
+        // TODO: handle exception
+        syslog(LOG_ERR, $e->getMessage());
+      }
+    }
+    return $trackId;
+  }
+
+  /**
+   * Add new position to track
+   *
+   * @param int $userId
+   * @param int $timestamp Unix time stamp
+   * @param double $lat
+   * @param double $lon
+   * @param double $altitude Optional
+   * @param double $speed Optional
+   * @param double $bearing Optional
+   * @param int $accuracy Optional
+   * @param string $provider Optional
+   * @param string $comment Optional
+   * @param int $imageId Optional
+   * @return int|bool New position id in database, false on error
+   */
+  public function addPosition($userId, $timestamp, $lat, $lon,
+                              $altitude = null, $speed = null, $bearing = null, $accuracy = null,
+                              $provider = null, $comment = null, $imageId = null) {
+    return uPosition::add($userId, $this->id, $timestamp, $lat, $lon,
+                                  $altitude, $speed, $bearing, $accuracy, $provider, $comment, $imageId);
+  }
+
+  /**
+   * Delete track with all positions
+   *
+   * @return bool True if success, false otherwise
+   */
+  public function delete() {
+    $ret = false;
+    if ($this->isValid) {
+      // delete positions
+      if (uPosition::deleteAll($this->userId, $this->id) === false) {
+        return false;
+      }
+      // delete track metadata
+      try {
+        $query = "DELETE FROM " . self::db()->table('tracks') . " WHERE id = ?";
+        $stmt = self::db()->prepare($query);
+        $stmt->execute([ $this->id ]);
+        $ret = true;
+        $this->id = null;
+        $this->userId = null;
+        $this->name = null;
+        $this->comment = null;
+        $this->isValid = false;
+      } catch (PDOException $e) {
+        // TODO: handle exception
+        syslog(LOG_ERR, $e->getMessage());
+      }
+    }
+    return $ret;
+  }
+
+  /**
+   * Update track
+   *
+   * @param string|null $name New name (not empty string) or null if not changed
+   * @param string|null $comment New comment or null if not changed (to remove content use empty string: "")
+   * @return bool True if success, false otherwise
+   */
+  public function update($name = null, $comment = null) {
+    $ret = false;
+    if (empty($name)) { $name = $this->name; }
+    if (is_null($comment)) { $comment = $this->comment; }
+    if ($comment === "") { $comment = null; }
+    if ($this->isValid) {
+      try {
+        $query = "UPDATE " . self::db()->table('tracks') . " SET name = ?, comment = ? WHERE id = ?";
+        $stmt = self::db()->prepare($query);
+        $params = [ $name, $comment, $this->id ];
+        $stmt->execute($params);
+        $ret = true;
+        $this->name = $name;
+        $this->comment = $comment;
+      } catch (PDOException $e) {
+        // TODO: handle exception
+        syslog(LOG_ERR, $e->getMessage());
+      }
+    }
+    return $ret;
+  }
+
+  /**
+   * Delete all user's tracks
+   *
+   * @param string $userId User id
+   * @return bool True if success, false otherwise
+   */
+  public static function deleteAll($userId) {
+    $ret = false;
+    if (!empty($userId) && uPosition::deleteAll($userId) === true) {
+      // remove all tracks
+      try {
+        $query = "DELETE FROM " . self::db()->table('tracks') . " WHERE user_id = ?";
+        $stmt = self::db()->prepare($query);
+        $stmt->execute([ $userId ]);
+        $ret = true;
+      } catch (PDOException $e) {
+        // TODO: handle exception
+        syslog(LOG_ERR, $e->getMessage());
+      }
+    }
+    return $ret;
+  }
+
+  /**
+   * Get all tracks
+   *
+   * @param int $userId Optional limit to user id
+   * @return array|bool Array of uTrack tracks, false on error
+   */
+  public static function getAll($userId = null) {
+    if (!empty($userId)) {
+      $where = "WHERE user_id=" . self::db()->quote($userId);
+    } else {
+      $where = "";
+    }
+    $query = "SELECT id, user_id, name, comment FROM " . self::db()->table('tracks') . " $where ORDER BY id DESC";
+    try {
+      $result = self::db()->query($query);
+      $trackArr = [];
+      while ($row = $result->fetch()) {
+        $trackArr[] = self::rowToObject($row);
+      }
+    } catch (PDOException $e) {
+      // TODO: handle exception
+      syslog(LOG_ERR, $e->getMessage());
+      $trackArr = false;
+    }
+    return $trackArr;
+  }
+
+  /**
+   * Convert database row to uTrack
+   *
+   * @param array $row Row
+   * @return uTrack Track
+    */
+  private static function rowToObject($row) {
+    $track = new uTrack();
+    $track->id = (int) $row['id'];
+    $track->userId = (int) $row['user_id'];
+    $track->name = $row['name'];
+    $track->comment = $row['comment'];
+    $track->isValid = true;
+    return $track;
+  }
+}
+
 ?>
\ No newline at end of file
diff --git a/helpers/upload.php b/helpers/upload.php
index ddbec56..d01546d 100644
--- a/helpers/upload.php
+++ b/helpers/upload.php
@@ -61,20 +61,20 @@ class uUpload {
   /**
    * Get file extension for given mime
    * @param $mime
-   * @return string|null Extension or NULL if not found
+   * @return string|null Extension or null if not found
    */
   private static function getExtension($mime) {
     if (self::isKnownMime($mime)) {
       return self::getMimeMap()[$mime];
     }
-    return NULL;
+    return null;
   }
 
   /**
    * Save file to uploads, basic sanitizing
    * @param array $uploaded File meta array from $_FILES[]
    * @param int $trackId
-   * @return string|NULL Unique file name, null on error
+   * @return string|null Unique file name, null on error
    */
   public static function add($uploaded, $trackId) {
     try {
@@ -82,7 +82,7 @@ class uUpload {
     } catch (Exception $e) {
       syslog(LOG_ERR, $e->getMessage());
       // save exception to txt file as image replacement?
-      return NULL;
+      return null;
     }
 
     $extension = self::getExtension($fileMeta[self::META_TYPE]);
@@ -93,7 +93,7 @@ class uUpload {
     if (move_uploaded_file($fileMeta[self::META_TMP_NAME], self::$uploadDir . $fileName)) {
       return $fileName;
     }
-    return NULL;
+    return null;
   }
 
   /**
@@ -140,7 +140,7 @@ class uUpload {
     $uploadErrors[UPLOAD_ERR_CANT_WRITE] = "Failed to write file to disk";
     $uploadErrors[UPLOAD_ERR_EXTENSION] = "A PHP extension stopped file upload";
 
-    $file = NULL;
+    $file = null;
     $fileError = isset($fileMeta[self::META_ERROR]) ? $fileMeta[self::META_ERROR] : UPLOAD_ERR_OK;
     if ($fileMeta[self::META_SIZE] > uUtils::getSystemUploadLimit() && $fileError == UPLOAD_ERR_OK) {
       $fileError = UPLOAD_ERR_FORM_SIZE;
diff --git a/helpers/user.php b/helpers/user.php
index b878343..67c5d87 100644
--- a/helpers/user.php
+++ b/helpers/user.php
@@ -20,222 +20,222 @@
   require_once(ROOT_DIR . "/helpers/track.php");
   require_once(ROOT_DIR . "/helpers/position.php");
 
- /**
-  * User handling routines
-  */
-  class uUser {
-    public $id;
-    public $login;
-    public $hash;
-    public $isAdmin = false;
-    public $isValid = false;
+/**
+ * User handling routines
+ */
+class uUser {
+  public $id;
+  public $login;
+  public $hash;
+  public $isAdmin = false;
+  public $isValid = false;
 
-   /**
-    * Constructor
-    *
-    * @param string $login Login
-    */
-    public function __construct($login = NULL) {
-      if (!empty($login)) {
-        try {
-          $query = "SELECT id, login, password, admin FROM " . self::db()->table('users') . " WHERE login = ? LIMIT 1";
-          $stmt = self::db()->prepare($query);
-          $stmt->execute([ $login ]);
-          $stmt->bindColumn('id', $this->id, PDO::PARAM_INT);
-          $stmt->bindColumn('login', $this->login);
-          $stmt->bindColumn('password', $this->hash);
-          $stmt->bindColumn('admin', $this->isAdmin, PDO::PARAM_BOOL);
-          if ($stmt->fetch(PDO::FETCH_BOUND)) {
-            $this->isValid = true;
-          }
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-      }
-    }
-
-    /**
-     * Get db instance
-     *
-     * @return uDb instance
-     */
-    private static function db() {
-      return uDb::getInstance();
-    }
-
-    /**
-     * Add new user
-     *
-     * @param string $login Login
-     * @param string $pass Password
-     * @param bool $isAdmin Is admin
-     * @return int|bool New user id, false on error
-     */
-    public static function add($login, $pass, $isAdmin = false) {
-      $userid = false;
-      if (!empty($login) && !empty($pass)) {
-        $hash = password_hash($pass, PASSWORD_DEFAULT);
-        $table = self::db()->table('users');
-        try {
-          $query = "INSERT INTO $table (login, password, admin) VALUES (?, ?, ?)";
-          $stmt = self::db()->prepare($query);
-          $stmt->execute([ $login, $hash, (int) $isAdmin ]);
-          $userid = (int) self::db()->lastInsertId("${table}_id_seq");
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-      }
-      return $userid;
-    }
-
-   /**
-    * Delete user
-    * This will also delete all user's positions and tracks
-    *
-    * @return bool True if success, false otherwise
-    */
-    public function delete() {
-      $ret = false;
-      if ($this->isValid) {
-        // remove tracks and positions
-        if (uTrack::deleteAll($this->id) === false) {
-          return false;
-        }
-        // remove user
-        try {
-          $query = "DELETE FROM " . self::db()->table('users') . " WHERE id = ?";
-          $stmt = self::db()->prepare($query);
-          $stmt->execute([ $this->id ]);
-          $ret = true;
-          $this->id = NULL;
-          $this->login = NULL;
-          $this->hash = NULL;
-          $this->isValid = false;
-          $this->isAdmin = false;
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-      }
-      return $ret;
-    }
-
-   /**
-    * Set user admin status
-    *
-    * @param bool $isAdmin True if is admin
-    * @return bool True on success, false otherwise
-    */
-    public function setAdmin($isAdmin) {
-      $ret = false;
+  /**
+   * Constructor
+   *
+   * @param string $login Login
+   */
+  public function __construct($login = null) {
+    if (!empty($login)) {
       try {
-        $query = "UPDATE " . self::db()->table('users') . " SET admin = ? WHERE login = ?";
+        $query = "SELECT id, login, password, admin FROM " . self::db()->table('users') . " WHERE login = ? LIMIT 1";
         $stmt = self::db()->prepare($query);
-        $stmt->execute([ (int) $isAdmin, $this->login ]);
-        $ret = true;
-        $this->isAdmin = $isAdmin;
-      } catch (PDOException $e) {
-        // TODO: handle exception
-        syslog(LOG_ERR, $e->getMessage());
-      }
-      return $ret;
-    }
-
-   /**
-    * Set user password
-    *
-    * @param string $pass Password
-    * @return bool True on success, false otherwise
-    */
-    public function setPass($pass) {
-      $ret = false;
-      if (!empty($this->login) && !empty($pass)) {
-        $hash = password_hash($pass, PASSWORD_DEFAULT);
-        try {
-          $query = "UPDATE " . self::db()->table('users') . " SET password = ? WHERE login = ?";
-          $stmt = self::db()->prepare($query);
-          $stmt->execute([ $hash, $this->login ]);
-          $ret = true;
-          $this->hash = $hash;
-        } catch (PDOException $e) {
-          // TODO: handle exception
-          syslog(LOG_ERR, $e->getMessage());
-        }
-      }
-      return $ret;
-    }
-
-   /**
-    * Check if given password matches user's one
-    *
-    * @param String $password Password
-    * @return bool True if matches, false otherwise
-    */
-    public function validPassword($password) {
-      return password_verify($password, $this->hash);
-    }
-
-   /**
-    * Store uUser object in session
-    */
-    public function storeInSession() {
-      $_SESSION['user'] = $this;
-    }
-
-   /**
-    * Fill uUser object properties from session data
-    * @return uUser
-    */
-    public static function getFromSession() {
-      $user = new uUser();
-      if (isset($_SESSION['user'])) {
-        $sessionUser = $_SESSION['user'];
-        $user->id = $sessionUser->id;
-        $user->login = $sessionUser->login;
-        $user->hash = $sessionUser->hash;
-        $user->isAdmin = $sessionUser->isAdmin;
-        $user->isValid = $sessionUser->isValid;
-      }
-      return $user;
-    }
-
-   /**
-    * Get all users
-    *
-    * @return uUser[]|bool Array of uUser users, false on error
-    */
-    public static function getAll() {
-      try {
-        $query = "SELECT id, login, password, admin FROM " . self::db()->table('users') . " ORDER BY login";
-        $result = self::db()->query($query);
-        $userArr = [];
-        while ($row = $result->fetch()) {
-          $userArr[] = self::rowToObject($row);
+        $stmt->execute([ $login ]);
+        $stmt->bindColumn('id', $this->id, PDO::PARAM_INT);
+        $stmt->bindColumn('login', $this->login);
+        $stmt->bindColumn('password', $this->hash);
+        $stmt->bindColumn('admin', $this->isAdmin, PDO::PARAM_BOOL);
+        if ($stmt->fetch(PDO::FETCH_BOUND)) {
+          $this->isValid = true;
         }
       } catch (PDOException $e) {
         // TODO: handle exception
         syslog(LOG_ERR, $e->getMessage());
-        $userArr = false;
       }
-      return $userArr;
-    }
-
-   /**
-    * Convert database row to uUser
-    *
-    * @param array $row Row
-    * @return uUser User
-    */
-    private static function rowToObject($row) {
-      $user = new uUser();
-      $user->id = (int) $row['id'];
-      $user->login = $row['login'];
-      $user->hash = $row['password'];
-      $user->isAdmin = (bool) $row['admin'];
-      $user->isValid = true;
-      return $user;
     }
   }
+
+  /**
+   * Get db instance
+   *
+   * @return uDb instance
+   */
+  private static function db() {
+    return uDb::getInstance();
+  }
+
+  /**
+   * Add new user
+   *
+   * @param string $login Login
+   * @param string $pass Password
+   * @param bool $isAdmin Is admin
+   * @return int|bool New user id, false on error
+   */
+  public static function add($login, $pass, $isAdmin = false) {
+    $userid = false;
+    if (!empty($login) && !empty($pass)) {
+      $hash = password_hash($pass, PASSWORD_DEFAULT);
+      $table = self::db()->table('users');
+      try {
+        $query = "INSERT INTO $table (login, password, admin) VALUES (?, ?, ?)";
+        $stmt = self::db()->prepare($query);
+        $stmt->execute([ $login, $hash, (int) $isAdmin ]);
+        $userid = (int) self::db()->lastInsertId("${table}_id_seq");
+      } catch (PDOException $e) {
+        // TODO: handle exception
+        syslog(LOG_ERR, $e->getMessage());
+      }
+    }
+    return $userid;
+  }
+
+  /**
+   * Delete user
+   * This will also delete all user's positions and tracks
+   *
+   * @return bool True if success, false otherwise
+   */
+  public function delete() {
+    $ret = false;
+    if ($this->isValid) {
+      // remove tracks and positions
+      if (uTrack::deleteAll($this->id) === false) {
+        return false;
+      }
+      // remove user
+      try {
+        $query = "DELETE FROM " . self::db()->table('users') . " WHERE id = ?";
+        $stmt = self::db()->prepare($query);
+        $stmt->execute([ $this->id ]);
+        $ret = true;
+        $this->id = null;
+        $this->login = null;
+        $this->hash = null;
+        $this->isValid = false;
+        $this->isAdmin = false;
+      } catch (PDOException $e) {
+        // TODO: handle exception
+        syslog(LOG_ERR, $e->getMessage());
+      }
+    }
+    return $ret;
+  }
+
+  /**
+   * Set user admin status
+   *
+   * @param bool $isAdmin True if is admin
+   * @return bool True on success, false otherwise
+   */
+  public function setAdmin($isAdmin) {
+    $ret = false;
+    try {
+      $query = "UPDATE " . self::db()->table('users') . " SET admin = ? WHERE login = ?";
+      $stmt = self::db()->prepare($query);
+      $stmt->execute([ (int) $isAdmin, $this->login ]);
+      $ret = true;
+      $this->isAdmin = $isAdmin;
+    } catch (PDOException $e) {
+      // TODO: handle exception
+      syslog(LOG_ERR, $e->getMessage());
+    }
+    return $ret;
+  }
+
+  /**
+   * Set user password
+   *
+   * @param string $pass Password
+   * @return bool True on success, false otherwise
+   */
+  public function setPass($pass) {
+    $ret = false;
+    if (!empty($this->login) && !empty($pass)) {
+      $hash = password_hash($pass, PASSWORD_DEFAULT);
+      try {
+        $query = "UPDATE " . self::db()->table('users') . " SET password = ? WHERE login = ?";
+        $stmt = self::db()->prepare($query);
+        $stmt->execute([ $hash, $this->login ]);
+        $ret = true;
+        $this->hash = $hash;
+      } catch (PDOException $e) {
+        // TODO: handle exception
+        syslog(LOG_ERR, $e->getMessage());
+      }
+    }
+    return $ret;
+  }
+
+  /**
+   * Check if given password matches user's one
+   *
+   * @param String $password Password
+   * @return bool True if matches, false otherwise
+   */
+  public function validPassword($password) {
+    return password_verify($password, $this->hash);
+  }
+
+  /**
+   * Store uUser object in session
+   */
+  public function storeInSession() {
+    $_SESSION['user'] = $this;
+  }
+
+  /**
+   * Fill uUser object properties from session data
+   * @return uUser
+   */
+  public static function getFromSession() {
+    $user = new uUser();
+    if (isset($_SESSION['user'])) {
+      $sessionUser = $_SESSION['user'];
+      $user->id = $sessionUser->id;
+      $user->login = $sessionUser->login;
+      $user->hash = $sessionUser->hash;
+      $user->isAdmin = $sessionUser->isAdmin;
+      $user->isValid = $sessionUser->isValid;
+    }
+    return $user;
+  }
+
+  /**
+   * Get all users
+   *
+   * @return uUser[]|bool Array of uUser users, false on error
+   */
+  public static function getAll() {
+    try {
+      $query = "SELECT id, login, password, admin FROM " . self::db()->table('users') . " ORDER BY login";
+      $result = self::db()->query($query);
+      $userArr = [];
+      while ($row = $result->fetch()) {
+        $userArr[] = self::rowToObject($row);
+      }
+    } catch (PDOException $e) {
+      // TODO: handle exception
+      syslog(LOG_ERR, $e->getMessage());
+      $userArr = false;
+    }
+    return $userArr;
+  }
+
+  /**
+   * Convert database row to uUser
+   *
+   * @param array $row Row
+   * @return uUser User
+   */
+  private static function rowToObject($row) {
+    $user = new uUser();
+    $user->id = (int) $row['id'];
+    $user->login = $row['login'];
+    $user->hash = $row['password'];
+    $user->isAdmin = (bool) $row['admin'];
+    $user->isValid = true;
+    return $user;
+  }
+}
 ?>
diff --git a/helpers/utils.php b/helpers/utils.php
index 402e06f..f82ab6a 100644
--- a/helpers/utils.php
+++ b/helpers/utils.php
@@ -17,211 +17,211 @@
  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
- /**
-  * Various util functions
-  */
-  class uUtils {
-
-    /**
-     * Calculate maximum allowed size of uploaded file
-     * for current PHP settings
-     *
-     * @return int Number of bytes
-     */
-    public static function getSystemUploadLimit() {
-      $upload_max_filesize = self::iniGetBytes('upload_max_filesize');
-      $post_max_size = self::iniGetBytes('post_max_size');
-      // post_max_size = 0 means unlimited size
-      if ($post_max_size === 0) { $post_max_size = $upload_max_filesize; }
-      $memory_limit = self::iniGetBytes('memory_limit');
-      // memory_limit = -1 means no limit
-      if ($memory_limit < 0) { $memory_limit = $post_max_size; }
-      return min($upload_max_filesize, $post_max_size, $memory_limit);
-    }
-
-    /**
-     * @param $path string Path
-     * @return bool True if is absolute
-     */
-    public static function isAbsolutePath($path) {
-      return $path[0] === '/' || $path[0] === '\\' || preg_match('/^[a-zA-Z]:\\\\/', $path);
-    }
-
-    /**
-     * Get number of bytes from ini parameter.
-     * Optionally parses shorthand byte values (G, M, B)
-     *
-     * @param string $iniParam Ini parameter name
-     * @return int Bytes
-     * @noinspection PhpMissingBreakStatementInspection
-     */
-    private static function iniGetBytes($iniParam) {
-      $iniStr = ini_get($iniParam);
-      $val = (float) $iniStr;
-      $suffix = substr(trim($iniStr), -1);
-      if (ctype_alpha($suffix)) {
-        switch (strtolower($suffix)) {
-          case 'g':
-            $val *= 1024;
-          case 'm':
-            $val *= 1024;
-          case 'k':
-            $val *= 1024;
-        }
-      }
-      return (int) $val;
-    }
-
-    /**
-     * Exit with error message
-     *
-     * @param string $errorMessage Message
-     * @param array|null $extra Optional array of extra parameters
-     */
-    public static function exitWithError($errorMessage, $extra = NULL) {
-      $extra['message'] = $errorMessage;
-      self::exitWithStatus(true, $extra);
-    }
-
-    /**
-     * Exit with successful status code
-     *
-     * @param array|null $extra Optional array of extra parameters
-     */
-    public static function exitWithSuccess($extra = NULL) {
-      self::exitWithStatus(false, $extra);
-    }
-
-    /**
-     * Exit with xml response
-     * @param boolean $isError Error if true
-     * @param array|null $extra Optional array of extra parameters
-     */
-    private static function exitWithStatus($isError, $extra = NULL) {
-      $output = [];
-      if ($isError) {
-        $output["error"] = true;
-      }
-      if (!empty($extra)) {
-        foreach ($extra as $key => $value) {
-          $output[$key] = $value;
-        }
-      }
-      header("Content-type: application/json");
-      echo json_encode($output);
-      exit;
-    }
-
-    /**
-     * Calculate app base URL
-     * Returned URL has trailing slash.
-     *
-     * @return string URL
-     */
-    public static function getBaseUrl() {
-      $proto = (!isset($_SERVER["HTTPS"]) || $_SERVER["HTTPS"] === "" || $_SERVER["HTTPS"] === "off") ? "http://" : "https://";
-      // Check if we are behind an https proxy
-      if (isset($_SERVER["HTTP_X_FORWARDED_PROTO"]) && $_SERVER["HTTP_X_FORWARDED_PROTO"] === "https") {
-        $proto = "https://";
-      }
-      $host = isset($_SERVER["HTTP_HOST"]) ? $_SERVER["HTTP_HOST"] : "";
-      if (realpath($_SERVER["SCRIPT_FILENAME"])) {
-        $scriptPath = substr(dirname(realpath($_SERVER["SCRIPT_FILENAME"])), strlen(ROOT_DIR));
-      } else {
-        // for phpunit
-        $scriptPath = substr(dirname($_SERVER["SCRIPT_FILENAME"]), strlen(ROOT_DIR));
-      }
-      $self = dirname($_SERVER["PHP_SELF"]);
-      $path = str_replace("\\", "/", substr($self, 0, strlen($self) - strlen($scriptPath)));
-
-      return $proto . str_replace("//", "/", $host . $path . "/");
-    }
-
-    public static function postFloat($name, $default = NULL) {
-      return self::requestValue($name, $default, INPUT_POST, FILTER_VALIDATE_FLOAT);
-    }
-
-    public static function getFloat($name, $default = NULL) {
-      return self::requestValue($name, $default, INPUT_GET, FILTER_VALIDATE_FLOAT);
-    }
-
-    public static function postPass($name, $default = NULL) {
-      return self::requestValue($name, $default, INPUT_POST);
-    }
-
-    public static function postString($name, $default = NULL) {
-      return self::requestString($name, $default, INPUT_POST);
-    }
-
-    public static function getString($name, $default = NULL) {
-      return self::requestString($name, $default, INPUT_GET);
-    }
-
-    public static function postBool($name, $default = NULL) {
-      $input = filter_input(INPUT_POST, $name, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);
-      return $input !== null ? (bool) $input : $default;
-    }
-
-    public static function getBool($name, $default = NULL) {
-      $input = filter_input(INPUT_GET, $name, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);
-      return $input !== null ? (bool) $input : $default;
-    }
-
-    public static function postInt($name, $default = NULL) {
-      return self::requestInt($name, $default, INPUT_POST);
-    }
-
-    public static function getInt($name, $default = NULL) {
-      return self::requestInt($name, $default, INPUT_GET);
-    }
-
-    public static function requestFile($name, $default = NULL) {
-      if (isset($_FILES[$name])) {
-        $files = $_FILES[$name];
-        if (isset($files["name"], $files["type"], $files["size"], $files["tmp_name"])) {
-          return $_FILES[$name];
-        }
-      }
-      return $default;
-    }
-
-    public static function postArray($name, $default = NULL) {
-      return ((isset($_POST[$name]) && is_array($_POST[$name])) ? $_POST[$name] : $default);
-    }
-
-    /**
-     * @param string $name Input name
-     * @param boolean $checkMime Optionally check mime with known types
-     * @return array File metadata array
-     * @throws Exception Upload exception
-     * @throws ErrorException Internal server exception
-     */
-    public static function requireFile($name, $checkMime = false) {
-      return uUpload::sanitizeUpload($_FILES[$name], $checkMime);
-    }
-
-    private static function requestString($name, $default, $type) {
-      if (is_string(($val = self::requestValue($name, $default, $type)))) {
-        return trim($val);
-      }
-      return $val;
-    }
-
-    private static function requestInt($name, $default, $type) {
-      if (is_float(($val = self::requestValue($name, $default, $type, FILTER_VALIDATE_FLOAT)))) {
-        return (int) round($val);
-      }
-      return self::requestValue($name, $default, $type, FILTER_VALIDATE_INT);
-    }
-
-    private static function requestValue($name, $default, $type, $filters = FILTER_DEFAULT, $flags = []) {
-      $input = filter_input($type, $name, $filters, $flags);
-      if ($input !== false && $input !== null) {
-        return $input;
-      }
-      return $default;
-    }
+/**
+ * Various util functions
+ */
+class uUtils {
 
+  /**
+   * Calculate maximum allowed size of uploaded file
+   * for current PHP settings
+   *
+   * @return int Number of bytes
+   */
+  public static function getSystemUploadLimit() {
+    $upload_max_filesize = self::iniGetBytes('upload_max_filesize');
+    $post_max_size = self::iniGetBytes('post_max_size');
+    // post_max_size = 0 means unlimited size
+    if ($post_max_size === 0) { $post_max_size = $upload_max_filesize; }
+    $memory_limit = self::iniGetBytes('memory_limit');
+    // memory_limit = -1 means no limit
+    if ($memory_limit < 0) { $memory_limit = $post_max_size; }
+    return min($upload_max_filesize, $post_max_size, $memory_limit);
   }
 
+  /**
+   * @param $path string Path
+   * @return bool True if is absolute
+   */
+  public static function isAbsolutePath($path) {
+    return $path[0] === '/' || $path[0] === '\\' || preg_match('/^[a-zA-Z]:\\\\/', $path);
+  }
+
+  /**
+   * Get number of bytes from ini parameter.
+   * Optionally parses shorthand byte values (G, M, B)
+   *
+   * @param string $iniParam Ini parameter name
+   * @return int Bytes
+   * @noinspection PhpMissingBreakStatementInspection
+   */
+  private static function iniGetBytes($iniParam) {
+    $iniStr = ini_get($iniParam);
+    $val = (float) $iniStr;
+    $suffix = substr(trim($iniStr), -1);
+    if (ctype_alpha($suffix)) {
+      switch (strtolower($suffix)) {
+        case 'g':
+          $val *= 1024;
+        case 'm':
+          $val *= 1024;
+        case 'k':
+          $val *= 1024;
+      }
+    }
+    return (int) $val;
+  }
+
+  /**
+   * Exit with error message
+   *
+   * @param string $errorMessage Message
+   * @param array|null $extra Optional array of extra parameters
+   */
+  public static function exitWithError($errorMessage, $extra = null) {
+    $extra['message'] = $errorMessage;
+    self::exitWithStatus(true, $extra);
+  }
+
+  /**
+   * Exit with successful status code
+   *
+   * @param array|null $extra Optional array of extra parameters
+   */
+  public static function exitWithSuccess($extra = null) {
+    self::exitWithStatus(false, $extra);
+  }
+
+  /**
+   * Exit with xml response
+   * @param boolean $isError Error if true
+   * @param array|null $extra Optional array of extra parameters
+   */
+  private static function exitWithStatus($isError, $extra = null) {
+    $output = [];
+    if ($isError) {
+      $output["error"] = true;
+    }
+    if (!empty($extra)) {
+      foreach ($extra as $key => $value) {
+        $output[$key] = $value;
+      }
+    }
+    header("Content-type: application/json");
+    echo json_encode($output);
+    exit;
+  }
+
+  /**
+   * Calculate app base URL
+   * Returned URL has trailing slash.
+   *
+   * @return string URL
+   */
+  public static function getBaseUrl() {
+    $proto = (!isset($_SERVER["HTTPS"]) || $_SERVER["HTTPS"] === "" || $_SERVER["HTTPS"] === "off") ? "http://" : "https://";
+    // Check if we are behind an https proxy
+    if (isset($_SERVER["HTTP_X_FORWARDED_PROTO"]) && $_SERVER["HTTP_X_FORWARDED_PROTO"] === "https") {
+      $proto = "https://";
+    }
+    $host = isset($_SERVER["HTTP_HOST"]) ? $_SERVER["HTTP_HOST"] : "";
+    if (realpath($_SERVER["SCRIPT_FILENAME"])) {
+      $scriptPath = substr(dirname(realpath($_SERVER["SCRIPT_FILENAME"])), strlen(ROOT_DIR));
+    } else {
+      // for phpunit
+      $scriptPath = substr(dirname($_SERVER["SCRIPT_FILENAME"]), strlen(ROOT_DIR));
+    }
+    $self = dirname($_SERVER["PHP_SELF"]);
+    $path = str_replace("\\", "/", substr($self, 0, strlen($self) - strlen($scriptPath)));
+
+    return $proto . str_replace("//", "/", $host . $path . "/");
+  }
+
+  public static function postFloat($name, $default = null) {
+    return self::requestValue($name, $default, INPUT_POST, FILTER_VALIDATE_FLOAT);
+  }
+
+  public static function getFloat($name, $default = null) {
+    return self::requestValue($name, $default, INPUT_GET, FILTER_VALIDATE_FLOAT);
+  }
+
+  public static function postPass($name, $default = null) {
+    return self::requestValue($name, $default, INPUT_POST);
+  }
+
+  public static function postString($name, $default = null) {
+    return self::requestString($name, $default, INPUT_POST);
+  }
+
+  public static function getString($name, $default = null) {
+    return self::requestString($name, $default, INPUT_GET);
+  }
+
+  public static function postBool($name, $default = null) {
+    $input = filter_input(INPUT_POST, $name, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);
+    return $input !== null ? (bool) $input : $default;
+  }
+
+  public static function getBool($name, $default = null) {
+    $input = filter_input(INPUT_GET, $name, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);
+    return $input !== null ? (bool) $input : $default;
+  }
+
+  public static function postInt($name, $default = null) {
+    return self::requestInt($name, $default, INPUT_POST);
+  }
+
+  public static function getInt($name, $default = null) {
+    return self::requestInt($name, $default, INPUT_GET);
+  }
+
+  public static function requestFile($name, $default = null) {
+    if (isset($_FILES[$name])) {
+      $files = $_FILES[$name];
+      if (isset($files["name"], $files["type"], $files["size"], $files["tmp_name"])) {
+        return $_FILES[$name];
+      }
+    }
+    return $default;
+  }
+
+  public static function postArray($name, $default = null) {
+    return ((isset($_POST[$name]) && is_array($_POST[$name])) ? $_POST[$name] : $default);
+  }
+
+  /**
+   * @param string $name Input name
+   * @param boolean $checkMime Optionally check mime with known types
+   * @return array File metadata array
+   * @throws Exception Upload exception
+   * @throws ErrorException Internal server exception
+   */
+  public static function requireFile($name, $checkMime = false) {
+    return uUpload::sanitizeUpload($_FILES[$name], $checkMime);
+  }
+
+  private static function requestString($name, $default, $type) {
+    if (is_string(($val = self::requestValue($name, $default, $type)))) {
+      return trim($val);
+    }
+    return $val;
+  }
+
+  private static function requestInt($name, $default, $type) {
+    if (is_float(($val = self::requestValue($name, $default, $type, FILTER_VALIDATE_FLOAT)))) {
+      return (int) round($val);
+    }
+    return self::requestValue($name, $default, $type, FILTER_VALIDATE_INT);
+  }
+
+  private static function requestValue($name, $default, $type, $filters = FILTER_DEFAULT, $flags = []) {
+    $input = filter_input($type, $name, $filters, $flags);
+    if ($input !== false && $input !== null) {
+      return $input;
+    }
+    return $default;
+  }
+
+}
+
 ?>
diff --git a/index.php b/index.php
index 4201515..bc72595 100644
--- a/index.php
+++ b/index.php
@@ -17,32 +17,32 @@
  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
-  require_once(__DIR__ . '/helpers/auth.php');
-  require_once(ROOT_DIR . '/helpers/config.php');
-  require_once(ROOT_DIR . '/helpers/position.php');
-  require_once(ROOT_DIR . '/helpers/track.php');
-  require_once(ROOT_DIR . '/helpers/utils.php');
-  require_once(ROOT_DIR . '/helpers/lang.php');
+require_once(__DIR__ . '/helpers/auth.php');
+require_once(ROOT_DIR . '/helpers/config.php');
+require_once(ROOT_DIR . '/helpers/position.php');
+require_once(ROOT_DIR . '/helpers/track.php');
+require_once(ROOT_DIR . '/helpers/utils.php');
+require_once(ROOT_DIR . '/helpers/lang.php');
 
-  $login = uUtils::postString('user');
-  $pass = uUtils::postPass('pass');
-  $action = uUtils::postString('action');
+$login = uUtils::postString('user');
+$pass = uUtils::postPass('pass');
+$action = uUtils::postString('action');
 
-  $config = uConfig::getInstance();
-  $lang = (new uLang($config))->getStrings();
-  $langsArr = uLang::getLanguages();
+$config = uConfig::getInstance();
+$lang = (new uLang($config))->getStrings();
+$langsArr = uLang::getLanguages();
 
-  $auth = new uAuth();
-  if ($action === 'auth') {
-    $auth->checkLogin($login, $pass);
-  }
+$auth = new uAuth();
+if ($action === 'auth') {
+  $auth->checkLogin($login, $pass);
+}
 
-  if ($action === 'auth' && !$auth->isAuthenticated()) {
-    $auth->exitWithRedirect('login.php?auth_error=1');
-  }
-  if ($config->requireAuthentication && !$auth->isAuthenticated()) {
-    $auth->exitWithRedirect('login.php');
-  }
+if ($action === 'auth' && !$auth->isAuthenticated()) {
+  $auth->exitWithRedirect('login.php?auth_error=1');
+}
+if ($config->requireAuthentication && !$auth->isAuthenticated()) {
+  $auth->exitWithRedirect('login.php');
+}
 
 ?>
 <!DOCTYPE html>
diff --git a/js/src/configdialogmodel.js b/js/src/configdialogmodel.js
index 21c516d..b66aa4d 100644
--- a/js/src/configdialogmodel.js
+++ b/js/src/configdialogmodel.js
@@ -199,7 +199,7 @@ export default class ConfigDialogModel extends ViewModel {
     }
     return `<div><img style="vertical-align: bottom; margin-right: 10px;" src="images/settings.svg" alt="${$._('settings')}"> <b>${$._('editingconfig')}</b></div>
       <div style="clear: both; padding-bottom: 1em;"></div>
-      <form id="configForm">
+      <form id="config-form">
         <label><b>${$._('language')}</b>
         <select data-bind="lang">
           ${langOptions}
diff --git a/scripts/import_cli.php b/scripts/import_cli.php
index 1c63ba1..658db35 100644
--- a/scripts/import_cli.php
+++ b/scripts/import_cli.php
@@ -138,7 +138,7 @@ foreach ($gpxFiles as $i => $gpxFile) {
   $trackCnt = 0;
   foreach ($gpx->trk as $trk) {
     $trackName = empty($trk->name) ? $gpxName : (string) $trk->name;
-    $metaName = empty($gpx->metadata->name) ? NULL : (string) $gpx->metadata->name;
+    $metaName = empty($gpx->metadata->name) ? null : (string) $gpx->metadata->name;
     $trackId = uTrack::add($userId, $trackName, $metaName);
     if ($trackId === false) {
       uUtils::exitWithError($lang["servererror"]);
@@ -154,10 +154,10 @@ foreach ($gpxFiles as $i => $gpxFile) {
           uUtils::exitWithError($lang["iparsefailure"]);
         }
         $time = isset($point->time) ? strtotime($point->time) : 0;
-        $altitude = isset($point->ele) ? (double) $point->ele : NULL;
-        $speed = NULL;
-        $bearing = NULL;
-        $accuracy = NULL;
+        $altitude = isset($point->ele) ? (double) $point->ele : null;
+        $speed = null;
+        $bearing = null;
+        $accuracy = null;
         $provider = "gps";
         if (!empty($point->extensions)) {
           // parse ulogger extensions
@@ -169,7 +169,7 @@ foreach ($gpxFiles as $i => $gpxFile) {
         }
         $ret = $track->addPosition($userId,
           $time, (double) $point["lat"], (double) $point["lon"], $altitude,
-          $speed, $bearing, $accuracy, $provider, NULL, NULL);
+          $speed, $bearing, $accuracy, $provider, null, null);
         if ($ret === false) {
           $track->delete();
           uUtils::exitWithError($lang["servererror"]);
diff --git a/utils/export.php b/utils/export.php
index 0a018d5..38de0a1 100644
--- a/utils/export.php
+++ b/utils/export.php
@@ -100,8 +100,8 @@ if ($trackId && $userId) {
       $xml->setIndent(true);
       $xml->startDocument("1.0", "utf-8");
       $xml->startElement("kml");
-      $xml->writeAttributeNs("xsi", "schemaLocation", NULL, "http://www.opengis.net/kml/2.2 http://schemas.opengis.net/kml/2.2.0/ogckml22.xsd");
-      $xml->writeAttributeNs("xmlns", "xsi", NULL, "http://www.w3.org/2001/XMLSchema-instance");
+      $xml->writeAttributeNs("xsi", "schemaLocation", null, "http://www.opengis.net/kml/2.2 http://schemas.opengis.net/kml/2.2.0/ogckml22.xsd");
+      $xml->writeAttributeNs("xmlns", "xsi", null, "http://www.w3.org/2001/XMLSchema-instance");
       $xml->writeAttribute("xmlns", "http://www.opengis.net/kml/2.2");
       $xml->startElement("Document");
       $xml->writeElement("name", $positionsArr[0]->trackName);
@@ -132,7 +132,7 @@ if ($trackId && $userId) {
         if(++$i === count($positionsArr)) { $style = "#greenStyle"; } // last element
         $xml->startElement("Placemark");
         $xml->writeAttribute("id", "point_{$position->id}");
-          $description =
+        $description =
           "<div style=\"font-weight: bolder; padding-bottom: 10px; border-bottom: 1px solid gray;\">" .
           "{$lang["user"]}: " . htmlspecialchars($position->userLogin) . "<br>{$lang["track"]}: " . htmlspecialchars($position->trackName) .
           "</div>" .
@@ -151,7 +151,7 @@ if ($trackId && $userId) {
           $xml->endElement();
           $xml->writeElement("styleUrl", $style);
           $xml->startElement("Point");
-            $coordinate[$i] = "{$position->longitude},{$position->latitude}" . (!is_null($position->altitude) ? ",{$position->altitude}" : "");
+          $coordinate[$i] = "{$position->longitude},{$position->latitude}" . (!is_null($position->altitude) ? ",{$position->altitude}" : "");
             $xml->writeElement("coordinates", $coordinate[$i]);
           $xml->endElement();
         $xml->endElement();
@@ -182,9 +182,9 @@ if ($trackId && $userId) {
       $xml->startDocument("1.0", "utf-8");
       $xml->startElement("gpx");
       $xml->writeAttribute("xmlns", "http://www.topografix.com/GPX/1/1");
-      $xml->writeAttributeNs("xsi", "schemaLocation", NULL, "http://www.topografix.com/GPX/1/1 http://www.topografix.com/GPX/1/1/gpx.xsd https://github.com/bfabiszewski/ulogger-android/1 https://raw.githubusercontent.com/bfabiszewski/ulogger-server/master/scripts/gpx_extensions1.xsd");
-      $xml->writeAttributeNs("xmlns", "xsi", NULL, "http://www.w3.org/2001/XMLSchema-instance");
-      $xml->writeAttributeNs("xmlns", "ulogger", NULL, "https://github.com/bfabiszewski/ulogger-android/1");
+      $xml->writeAttributeNs("xsi", "schemaLocation", null, "http://www.topografix.com/GPX/1/1 http://www.topografix.com/GPX/1/1/gpx.xsd https://github.com/bfabiszewski/ulogger-android/1 https://raw.githubusercontent.com/bfabiszewski/ulogger-server/master/scripts/gpx_extensions1.xsd");
+      $xml->writeAttributeNs("xmlns", "xsi", null, "http://www.w3.org/2001/XMLSchema-instance");
+      $xml->writeAttributeNs("xmlns", "ulogger", null, "https://github.com/bfabiszewski/ulogger-android/1");
       $xml->writeAttribute("creator", "μlogger-server " . $config->version);
       $xml->writeAttribute("version", "1.1");
       $xml->startElement("metadata");
@@ -194,46 +194,47 @@ if ($trackId && $userId) {
       $xml->startElement("trk");
         $xml->writeElement("name", $positionsArr[0]->trackName);
         $xml->startElement("trkseg");
-        $i = 0;
-        $totalMeters = 0;
-        $totalSeconds = 0;
-        foreach ($positionsArr as $position) {
-          $distance = isset($prevPosition) ? $position->distanceTo($prevPosition) : 0;
-          $seconds = isset($prevPosition) ? $position->secondsTo($prevPosition) : 0;
-          $prevPosition = $position;
-          $totalMeters += $distance;
-          $totalSeconds += $seconds;
+      $i = 0;
+      $totalMeters = 0;
+      $totalSeconds = 0;
+      foreach ($positionsArr as $position) {
+        $distance = isset($prevPosition) ? $position->distanceTo($prevPosition) : 0;
+        $seconds = isset($prevPosition) ? $position->secondsTo($prevPosition) : 0;
+        $prevPosition = $position;
+        $totalMeters += $distance;
+        $totalSeconds += $seconds;
           $xml->startElement("trkpt");
             $xml->writeAttribute("lat", $position->latitude);
             $xml->writeAttribute("lon", $position->longitude);
-            if (!is_null($position->altitude)) { $xml->writeElement("ele", $position->altitude); }
+        if (!is_null($position->altitude)) { 
+            $xml->writeElement("ele", $position->altitude); 
+        }
             $xml->writeElement("time", gmdate("Y-m-d\TH:i:s\Z", $position->timestamp));
             $xml->writeElement("name", ++$i);
-            if (!is_null($position->comment)) {
-              $xml->startElement("desc");
+        if (!is_null($position->comment)) {
+            $xml->startElement("desc");
               $xml->writeCData($position->comment);
-              $xml->endElement();
-            }
-            if (!is_null($position->speed) || !is_null($position->bearing) || !is_null($position->accuracy) || !is_null($position->provider)) {
-              $xml->startElement("extensions");
-
-              if (!is_null($position->speed)) {
-                $xml->writeElementNS("ulogger", "speed", NULL, $position->speed);
-              }
-              if (!is_null($position->bearing)) {
-                $xml->writeElementNS("ulogger", "bearing", NULL, $position->bearing);
-              }
-              if (!is_null($position->accuracy)) {
-                $xml->writeElementNS("ulogger", "accuracy", NULL, $position->accuracy);
-              }
-              if (!is_null($position->provider)) {
-                $xml->writeElementNS("ulogger", "provider", NULL, $position->provider);
-              }
-
-              $xml->endElement();
-            }
-          $xml->endElement();
+            $xml->endElement();
         }
+        if (!is_null($position->speed) || !is_null($position->bearing) || !is_null($position->accuracy) || !is_null($position->provider)) {
+            $xml->startElement("extensions");
+
+          if (!is_null($position->speed)) {
+              $xml->writeElementNS("ulogger", "speed", null, $position->speed);
+          }
+          if (!is_null($position->bearing)) {
+              $xml->writeElementNS("ulogger", "bearing", null, $position->bearing);
+          }
+          if (!is_null($position->accuracy)) {
+              $xml->writeElementNS("ulogger", "accuracy", null, $position->accuracy);
+          }
+          if (!is_null($position->provider)) {
+              $xml->writeElementNS("ulogger", "provider", null, $position->provider);
+          }
+            $xml->endElement();
+        }
+          $xml->endElement();
+      }
         $xml->endElement();
       $xml->endElement();
       $xml->endElement();
diff --git a/utils/handleuser.php b/utils/handleuser.php
index 1c8c06e..5fe3eca 100644
--- a/utils/handleuser.php
+++ b/utils/handleuser.php
@@ -41,7 +41,7 @@ if ($admin && !$auth->isAdmin()) {
 }
 
 $aUser = new uUser($login);
-$data = NULL;
+$data = null;
 
 switch ($action) {
   case 'add':
diff --git a/utils/import.php b/utils/import.php
index 9ec9f3c..5219b6e 100644
--- a/utils/import.php
+++ b/utils/import.php
@@ -73,7 +73,7 @@ else if (empty($gpx->trk)) {
 $trackList = [];
 foreach ($gpx->trk as $trk) {
   $trackName = empty($trk->name) ? $gpxName : (string) $trk->name;
-  $metaName = empty($gpx->metadata->name) ? NULL : (string) $gpx->metadata->name;
+  $metaName = empty($gpx->metadata->name) ? null : (string) $gpx->metadata->name;
   $trackId = uTrack::add($auth->user->id, $trackName, $metaName);
   if ($trackId === false) {
     uUtils::exitWithError($lang["servererror"]);
@@ -89,11 +89,11 @@ foreach ($gpx->trk as $trk) {
         uUtils::exitWithError($lang["iparsefailure"]);
       }
       $time = isset($point->time) ? strtotime($point->time) : 1;
-      $altitude = isset($point->ele) ? (double) $point->ele : NULL;
-      $comment = isset($point->desc) && !empty($point->desc) ? (string) $point->desc : NULL;
-      $speed = NULL;
-      $bearing = NULL;
-      $accuracy = NULL;
+      $altitude = isset($point->ele) ? (double) $point->ele : null;
+      $comment = isset($point->desc) && !empty($point->desc) ? (string) $point->desc : null;
+      $speed = null;
+      $bearing = null;
+      $accuracy = null;
       $provider = "gps";
       if (!empty($point->extensions)) {
         // parse ulogger extensions
@@ -105,7 +105,7 @@ foreach ($gpx->trk as $trk) {
       }
       $ret = $track->addPosition($auth->user->id,
                     $time, (double) $point["lat"], (double) $point["lon"], $altitude,
-                    $speed, $bearing, $accuracy, $provider, $comment, NULL);
+                    $speed, $bearing, $accuracy, $provider, $comment, null);
       if ($ret === false) {
         $track->delete();
         uUtils::exitWithError($lang["servererror"]);