[Wintamute]

You don't need an internet connection to get a GPS fix, so this app would work fine anywhere I think. You then need internet connectivity to sync your accumulated lat/long data back to your account.

[vhf]

Not only you don't need an internet connection to get a GPS fix, but also iPhones geolocation data don't rely on GPS only.

http://en.wikipedia.org/wiki/Assisted_GPS