I will getting my wife an iPhone. I want it to run OS 4.0 for multi-tasking. She is used to using the 8320, wifi access mostly for FaceBook. She also txts a great deal. We don't have a data plan but will want to get one. Can I just buy a new iPhone off eBay? We don't want to change our current contract any, just add data to it so that is why I don't want to buy the iPhone through ATT.