I have an Android application which I hope to promote in developing/emerging markets for crowdsourced mobile work. Reliable location detection is a major part of some of the scenarios.
I understand that mobile location-based solutions use a variety of signals to detect the user's current position:
- Traditional satellite GPS, frequently assisted via aGPS
- Google's database of wifi routers and their locations
- Google's database of cell tower IDs and their locations
Satellite coverage is of course global, but how is the International coverage for #2 and #3? Is there any service I can consult to gauge (even anecdotally) the coverage of Google's location databases around the world? Even a (data-backed) report or blot post would be helpful.
The key issue I face is whether to require a mobile data plan for users of my application (and whether a mobile data plan would actually help location accuracy in certain markets). If mobile internet/data will make a huge impact on location accuracy, then it makes sense to require it ... but otherwise I want to support wifi-only scenarios.