You probably know that the iPhone 4S does not have the option to disable 3G connectivity in the iOS settings menu, as the rest of the iPhones produced by Apple have. So far, no one has given any official explanation regarding the lack of that option, but in general, most say that 3G is left permanently active so that Siri can work properly. Well, for others there are slightly more "professional" explanations for the lack of that option and recently I heard that the modem in the iPhone 4S would not be able to close the 3G connection and the lack of that option would be due to this problem.
If the statement was true, then the 4S would have worked exclusively on 3G connections, not on EDGE/GPRS ones, so you could not have used it outside the big cities. Leaving aside the bad explanation regarding the lack of option, I remind you that ONLY on the iPhone 4S you cannot turn off 3G connectivity, the rest of the iPhones still have this option.
