Very impressive! Some comments and quick features I think will be helpful to complete the experience though:
- The red dot is a great idea! I used to find it hard when trying to zoom for the farthest zoom level (globe view) to just a single town in a country.
- Would be nice if it could remember the current position until next launch
- Double-tapping with stylus to zoom
- Searching and POIs would be helpful, but I suppose may still be too early. :P

I've been playing around with the python-gpsbt bindings, it should be rather trivial to add GPS support. Let me see if I can write a patch for it.