my son currently has an iphone 4 here in the US. he is about to spend 4 months studying in London. he wants to continue using an iphone while in london, but att's international phone and data rates are just too expensive. 1 -i am trying to figure out how to hack, 2 - if its better to hack his old iphone 3 or my old 3gs. 3- once one of these phones is hacked, what service does he use so he can use the phone, search the web and send international texts and how much it will cost. 4 - lastly, once the phone is set up to work in london, does he not update itunes or if he does will the iphone stop working. thank you and happy holidays to all.