[tocomment]

Phones don't really have GPS though, right? And there's no easy way to write software that uses it even if it is there.

[nirs]

The phone network can locate your phone - so your phone can also know its location even without GPS. If your phone knows your location, and is connected to the web, it can work.

[tocomment]

If you can tell me how to do this using only a website (no phone specific programming) it would dovetail nicely into a startup idea I'm considering.

I figured it would require getting users to install my software on their phone somehow, dealing with phone companies, and learning something called "Symbian".