How can I know an iPhone is factory unlocked from Apple or under-contract/off-contract unlocked iPhone ( when I buy an New phone in an open box)
I bought an new iphone 5 in an open box through craiglist. When a guy showed me the phone, I saw it was using T-mobile sim card with 3G. So I think it is unlock. then I went to a website that checks status of iphones using IMEI, I see the phone is lock, but I didn't see any carrier in information, then I put another IMEI (locked phone) I saw carrier is At&t
So, how can I know for sure is the phone is unlock factory (original buy from apple or reliable retailers)
I also see on ebay, some sellers do factory unlock for couple of dollars
iPhone 5, iOS 6.0.2