Originally Posted by
milepig
But most reports are that for GPS to work on a plane you have to hold the unit right up against the window, making it pretty obvious what you're doing. The GPS on my phone and ITouch pretty much don't work inside at all.
A lot of those small devices require the loading of maps to show positions, and that needs some sort of internet connection. You could get exact coordinates of course with no map needed, but on devices like the IPhone, the Google Maps GPS feature won't be of much use if the device can't load the correct map.