This library uses geolocation to add a marker and accuracy circle to a map. The marker position is automatically updated as the user position changes.

To add the Geolocation Marker, just instantiate a new GeolocationMarker object, passing the constructor your map object:

var mapOptions = {
  zoom: 17,
  center: new google.maps.LatLng(-34.397, 150.644),
  mapTypeId: google.maps.MapTypeId.ROADMAP
};
var map = new google.maps.Map(document.getElementById('map_canvas'),
    mapOptions);
var GeoMarker = new GeolocationMarker(map);

See the example.

Note: This library will only function in browsers supporting the W3C Geolocation API. This excludes Internet Explorer versions 8 and older.

Reference documentation