Location tracking on iOS devices without GPS (for example an iPod touch) sometimes works without any internet connection (it nearly always works with an internet connection – WLAN access points are used to determine the approximate location), especially in urban environments (with a lot of WLAN access points). I always figured that iOS devices download location info on all the surrounding WLAN access points (maybe even those not in range – it seemed like that in my tests) as soon as you use location services and are connected to the internet.
This database could have something to do with that.
This database could have something to do with that.