Send gps coordinates to server every minute - jquery-mobile

Question

I'm tyring to build a PhoneGap app with jQueryMobile. In my app I need to send a users current geolocations GPS coordinates to server every 4 minute. How can I do this?
This is the code I have been using right now, but it doesn't send any data. How can i modify this to make it work?
document.addEventListener("deviceready", onDeviceReady, false);
var watchID = null;
// PhoneGap is ready
//
function onDeviceReady() {
// Update every 4 minute
var options = { maximumAge: 240000, timeout: 5000, enableHighAccuracy: true };
watchID = navigator.geolocation.watchPosition(onSuccess, onError, options);
}
// onSuccess Geolocation
//
function onSuccess(position) {
var lat = Position.coords.latitude;
var lng = Position.coords.longitude;
jQuery.ajax({
type: "POST",
url: serviceURL+"locationUpdate.php",
data: 'x='+lng+'&y='+lat,
cache: false
});
}
// onError Callback receives a PositionError object
//
function onError(error) {
alert('code: ' + error.code + '\n' +
'message: ' + error.message + '\n');
}

Answer 1

Instead of calling setInterval, let phonegap do that for you.
// onSuccess Callback
// This method accepts a `Position` object, which contains the current GPS coordinates
//
function onSuccess(position) {
var element = document.getElementById('geolocation');
element.innerHTML = 'Latitude: ' + position.coords.latitude + '<br />' +
'Longitude: ' + position.coords.longitude + '<br />' +
'<hr />' + element.innerHTML;
}
// onError Callback receives a PositionError object
//
function onError(error) {
alert('code: ' + error.code + '\n' +
'message: ' + error.message + '\n');
}
// Options: retrieve the location every 3 seconds
//
var watchID = navigator.geolocation.watchPosition(onSuccess, onError, { frequency: 3000 });
http://docs.phonegap.com/en/1.0.0/phonegap_geolocation_geolocation.md.html#geolocation.watchPosition