diff --git a/js/admin.js b/js/admin.js
index 80357c5..13c979a 100644
--- a/js/admin.js
+++ b/js/admin.js
@@ -83,7 +83,7 @@ function submitUser(action) {
   xhr.onreadystatechange = function() {
     if (xhr.readyState == 4) {
       var error = true;
-      var message = "";
+      var message = '';
       if (xhr.status == 200) {
         var xml = xhr.responseXML;
         if (xml) {
diff --git a/js/api_gmaps.js b/js/api_gmaps.js
index a546617..0974ac1 100755
--- a/js/api_gmaps.js
+++ b/js/api_gmaps.js
@@ -40,7 +40,7 @@ function init() {
     mapTypeId: google.maps.MapTypeId.ROADMAP,
     scaleControl: true
   };
-  map = new google.maps.Map(document.getElementById("map-canvas"), mapOptions);
+  map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
 }
 function cleanup() {
   map = undefined;
@@ -50,7 +50,7 @@ function cleanup() {
   popup = undefined;
   polyOptions = undefined;
   mapOptions = undefined;
-  document.getElementById("map-canvas").innerHTML = '';
+  document.getElementById('map-canvas').innerHTML = '';
 }
 
 function displayTrack(xml, update) {
@@ -188,7 +188,7 @@ function zoomToBounds(b) {
 
 function gm_authFailure() {
   gm_error = true;
-  message = sprintf(lang['apifailure'], "Google Maps");
+  message = sprintf(lang['apifailure'], 'Google Maps');
   message += '<br><br>' + lang['gmauthfailure'];
   message += '<br><br>' + lang['gmapilink'];
   showModal(message);
diff --git a/js/api_openlayers.js b/js/api_openlayers.js
index b4677bc..248c673 100755
--- a/js/api_openlayers.js
+++ b/js/api_openlayers.js
@@ -185,7 +185,7 @@ function init() {
   });
 
   // change mouse cursor when over marker
-  map.on("pointermove", function(e) {
+  map.on('pointermove', function(e) {
     var hit = map.forEachFeatureAtPixel(e.pixel, function(feature, layer) {
       if (layer.get('name') == 'Markers') {
         return true;
@@ -287,7 +287,7 @@ function cleanup() {
   olStyles = undefined;
   removeElementById('popup');
   removeElementById('switcher');
-  document.getElementById("map-canvas").innerHTML = '';
+  document.getElementById('map-canvas').innerHTML = '';
 }
 
 function displayTrack(xml, update) {
diff --git a/js/main.js b/js/main.js
index f21c27f..d377fb0 100755
--- a/js/main.js
+++ b/js/main.js
@@ -135,7 +135,7 @@ function getXHR() {
 }
 
 function loadTrack(userid, trackid, update) {
-  var title = document.getElementById("track").getElementsByClassName("menutitle")[0];
+  var title = document.getElementById('track').getElementsByClassName('menutitle')[0];
   if (trackid < 0) { return; }
   if (latest == 1) { trackid = 0; }
   var xhr = getXHR();
@@ -262,7 +262,7 @@ function exportFile(type, userid, trackid) {
 
 function importFile(input) {
   var form = input.parentElement;
-  var title = form.parentElement.getElementsByClassName("menutitle")[0];
+  var title = form.parentElement.getElementsByClassName('menutitle')[0];
   var sizeMax = form.elements['MAX_FILE_SIZE'].value;
   if (input.files && input.files.length == 1 && input.files[0].size > sizeMax) {
     alert(sprintf(lang['isizefailure'], sizeMax));
@@ -272,7 +272,7 @@ function importFile(input) {
   xhr.onreadystatechange = function() {
     if (xhr.readyState == 4) {
       var error = true;
-      var message = "";
+      var message = '';
       if (xhr.status == 200) {
         var xml = xhr.responseXML;
         if (xml) {
@@ -298,9 +298,9 @@ function importFile(input) {
       xhr = null;
     }
   }
-  xhr.open("POST", "utils/import.php", true);
+  xhr.open('POST', 'utils/import.php', true);
   xhr.send(new FormData(form));
-  input.value = "";
+  input.value = '';
   setLoader(title);
 }
 
@@ -400,7 +400,7 @@ function selectUser(f) {
 }
 
 function getTracks(userid, trackid) {
-  var title = document.getElementById("track").getElementsByClassName("menutitle")[0];
+  var title = document.getElementById('track').getElementsByClassName('menutitle')[0];
   var xhr = getXHR();
   xhr.onreadystatechange = function () {
     if (xhr.readyState == 4) {
@@ -431,7 +431,7 @@ function fillOptions(xml, uid, tid) {
   for (var i = 0; i < trackLen; i++) {
     var trackid = getNode(tracks[i], 'trackid');
     var trackname = getNode(tracks[i], 'trackname');
-    var option = document.createElement("option");
+    var option = document.createElement('option');
     option.value = trackid;
     option.innerHTML = htmlEncode(trackname);
     trackSelect.appendChild(option);
diff --git a/js/pass.js b/js/pass.js
index 95723d7..651dafc 100644
--- a/js/pass.js
+++ b/js/pass.js
@@ -48,14 +48,14 @@ function submitPass() {
   xhr.onreadystatechange = function () {
     if (xhr.readyState == 4) {
       var error = true;
-      var message = "";
+      var message = '';
       if (xhr.status == 200) {
         var xml = xhr.responseXML;
         if (xml) {
           var root = xml.getElementsByTagName('root');
           if (root.length && getNode(root[0], 'error') == 0) {
             removeModal();
-            alert(lang["actionsuccess"]);
+            alert(lang['actionsuccess']);
             error = false;
           } else if (root.length) {
             errorMsg = getNode(root[0], 'message');
diff --git a/js/track.js b/js/track.js
index c9c98a7..bbdb38c 100644
--- a/js/track.js
+++ b/js/track.js
@@ -67,7 +67,7 @@ function submitTrack(action) {
   xhr.onreadystatechange = function() {
     if (xhr.readyState == 4) {
       var error = true;
-      var message = "";
+      var message = '';
       if (xhr.status == 200) {
         var xml = xhr.responseXML;
         if (xml) {