I have an iphone that I purchased from an individual. It was unlocked and jailbroken so I inserted my SIM card and everything worked. I was told it was 2G. After I started using it, I discovered it had GPS and was accessing the 3G network. After a couple of days, it would no longer access the 3G network (Edge instead) but the GPS continues to work. Since AT&T is my carrier, I restored the iphone using itunes. I then went online and changed my data plan from the $15 standard to the $20 iphone plan. All that process worked fine and of course the phone is now locked, unjailbroken, and legal. The other three things I should mention is that my serial number is printed on the back of my phone which I understand is indicative of a 2G, my serial number begins with 5K which I understand is indicative of a refurbished phone, and there is no menu item to turn on or off the 3G feature. The phone works fine and I am entirely happy with it but having the inquisitive mind that I do, I am curious as to exactly what it is I have. Thanks in advance for any help I can get.