Yes, I did. I created a sample App, installed it on my phone, and then moved about 500m. The change in location was reflected on the map.
Same as Darren. When I was using my solution, I would often test it while driving or walking around the block. As the distance column values change, it causes the javascript to run the calculation again with the new distance values. So as long as you are parming the distance into the javascript, it should continuously update your location.
Just be sure you are testing with a device that actually has a GPS in it. When I tested with my laptop, it would often be a static location that may occasionally jump. It may have been geolocating based on wifi access points or IP address.