I currently have at&t with about ten months left on my contract and my upgrade date only a month before that, so getting an iphone with my current at&t account would cost the full price.... With that said If i go to BestBuy Or wallmart and buy an Iphone 3g with a two year contract then call at&t and cancel within the first thirty days could i keep the iphone...? i know if i go into an at&t store they will want the phone back but how would best buy or wallmart know i canceled the contract????