diff --git a/helpers/db.php b/helpers/db.php
index 195589d..adbfc3c 100644
--- a/helpers/db.php
+++ b/helpers/db.php
@@ -26,7 +26,7 @@
     /**
      * Singleton instance
      *
-     * @var mysqli Object instance
+     * @var uDb Object instance
      */
     protected static $instance;
 
@@ -40,7 +40,7 @@
     /**
      * Database driver name
      *
-     * @var String Driver
+     * @var string Driver
      */
     protected static $driver;
 
@@ -82,7 +82,7 @@
    /**
     * Returns singleton instance
     *
-    * @return object Singleton instance
+    * @return uDb Singleton instance
     */
     public static function getInstance() {
       if (!self::$instance) {
diff --git a/helpers/position.php b/helpers/position.php
index 08e43f3..887e39e 100644
--- a/helpers/position.php
+++ b/helpers/position.php
@@ -89,10 +89,7 @@
      * @return uDb instance
      */
     private static function db() {
-      if (is_null(self::$db)) {
-        self::$db = uDb::getInstance();
-      }
-      return self::$db;
+      return uDb::getInstance();
     }
 
    /**
diff --git a/helpers/track.php b/helpers/track.php
index 3dbdb67..3e7eacc 100644
--- a/helpers/track.php
+++ b/helpers/track.php
@@ -31,6 +31,9 @@
 
     public $isValid = false;
 
+    /**
+     * @var uDb $db
+     */
     private static $db = null;
 
    /**
@@ -66,10 +69,7 @@
      * @return uDb instance
      */
     private static function db() {
-      if (is_null(self::$db)) {
-        self::$db = uDb::getInstance();
-      }
-      return self::$db;
+      return uDb::getInstance();
     }
 
    /**
@@ -102,7 +102,7 @@
      * Add new position to track
      *
      * @param int $userId
-     * @param int $time Unix time stamp
+     * @param int $timestamp Unix time stamp
      * @param double $lat
      * @param double $lon
      * @param double $altitude Optional
diff --git a/helpers/user.php b/helpers/user.php
index b35a115..7496829 100644
--- a/helpers/user.php
+++ b/helpers/user.php
@@ -67,10 +67,7 @@
      * @return uDb instance
      */
     private static function db() {
-      if (is_null(self::$db)) {
-        self::$db = uDb::getInstance();
-      }
-      return self::$db;
+      return uDb::getInstance();
     }
 
    /**