Geolocation GetCurrentPosition vs WatchPosition (HTML5 JavaScript ASP.NET MVC)

I'm creating some tracking functionality for a client who wants to be able to see a driver's progress on a map for deliveries. I have a javascript page in my APS.NET MVC4 application that has a one minue timer that gets the mobile user's current location every minute then stores that value in variables, then with a ajax makes a call into an MVC controller function that saves that location data into a database. Then the location data can be viewed on a bing map.

Did I implement this the correct way, or should I be using the HTML5 WatchPosition function instead of the GetCurrentPosition function? I did not see a way to set an interval in the WatchPosition function, it seems to fire every time the location changes which seems like it would be continuously firing, I only need the location data every minute or so. Thanks for your suggestions on my code below.

    var Latitude = 0;
    var Longitude = 0;

    var TrackingLoop = setInterval(function () { GetCurrentLocation() }, 60000);

    function RestartTracking() { location.reload(); }

    function GetCurrentLocation() {            
        if (navigator.geolocation) {
            var timeoutVal = 10 * 1000 * 1000;
            navigator.geolocation.getCurrentPosition(
                displayPosition,
                displayError,
                { enableHighAccuracy: true, timeout: timeoutVal, maximumAge: 0 }
            );
        }
        else {
            alert("Geolocation is not supported by this browser");
        }
    }


    function displayPosition(position) {
        Latitude = position.coords.latitude;
        Longitude = position.coords.longitude;
        UpdateLocation(Latitude, Longitude);
    }


    function UpdateLocation(Latitude, Longitude) {

        var JobID = document.getElementById("JobID").value;

        $.ajax({
            url: '/Job/UpdateLocation',
            type: 'POST',
            data: {
                JobID: JobID,
                Latitude: Latitude,
                Longitude: Longitude
            },
        });
    }