I also have Google Mobile Maps and I dont believe that can be edited. When I did some reasearch on this feature, it was explained to me that the "My Location" feature works off of your position triangulated (hope I spelled that right) of your phone in reference to the closest cell tower. Although this is not as pinpoint accurate as GPS, it pretty darn close. I have used it for about week and a half now and the my location feature is very welcomed feature.