So I recently lost my iPhone, or so I thought. I bought another one at full price and had my Att service switched over to the new phone. Well fast forward 2 months and the lost phone turns back up. I can't return the new one. The old one is still in decent shape. So I'm thinking about letting a friend use it temporarily because her 3G is falling apart and she needs something to hold her over till iPhone 5 comes out. Can I just plug this old iPhone into iTunes and let it do the account setup on her account using my old sim and everything? Or am I going to have to go to Att for help with this?