teamSVTour
Hard-core CEG'er
I'm not too sure anout the iPhone, but a data connection is needed to download maps and POIs while using GPS on most smart phones. I've never had a gps "signal" where I hadn't cell coverage, so I cannot confirm it. Just what I read :shrug:.
TomTom for iphone you DL all the maps and they are stored on the phone. The app is over 1G. So you just need to be in view of a the sky/satellite and your golden even with zero reception.