I have an iPhone 3G S and also have a ballistics calculator on it called Ballistic FTE, it only costs 8dollars, a real bargin! You don't need coverage to use most apps, some apps use your location but it's optional. None of mine need coverage, but seeing how many there are, logic says some will. The calculator is great, very accurate and generaly I love the iPhone, the texting keyboard is late out like that of a computer so once you ge used to it it's real fast. Having 3G (Internet) everywhere is also real useful. I was in the gun store today and the .30cal 175 Berger vlds were 56$ for 100! I ordered some off midway for 42 while still in the store.
Oliver