Sending data from mobile phone to node,js-Mongo server

I'm building a hybrid app using HTML 5 geoLocation and jQuery-mobile, when trying to send data to my server from a web browser the data sending\receiving works great but when i change the web browser to my mobile phone web browser the data at the server side is "NaN" - not a number(Node parsing i believe) :

[CastError: cast to number failed for value "NaN" at path "QueryCasting"]

The request is ajax-jquery that include the geoLocation:

if (navigator.geolocation) {
        navigator.geolocation.getCurrentPosition(showPosition, showError);
        }
    function showPosition(position) {
            currentLatitude = position.coords.latitude;
            currentLongitude = position.coords.longitude;                           
            localStorage.DeviceLocation=currentLatitude+","+currentLongitude;                                                   
        }   

Anyone tried to send geoLocation data to a node.js-mongoDB server, I suspect that the problem is in the currentLatitude, currentLongitude vars. Important thing is the phone browser isn't requesting me for my permission to use location. Before sending the data, I use .serializeJSON() I dont know if the problem is related to that, again I must say that the app is working fine on a laptop browser. Here is my jQuery-ajax request :

$('#GoButton').click (function () {
        var workerData = $("#workerForm").serializeJSON();
        workerData.lat = currentLatitude;
        workerData.lng = currentLongitude;
        $.ajax({
              type: "GET",
              dataType:'json',  // to json once server side is OK
              data: {valArray:workerData},    
              crossDomain: true,
              url:'http://ift.tt/1NWOGA3',
              //handle response - checks json format, statueCode (200,304)

Maybe the problem is with the request? or the crossDomain: true?

Thank you.