How to sell unlocked AT&T iPhone 3GS.

[chevy57]

I never used old iPhone 3GS when I have iPhone 4 now. I consider to sell AT&T IPhone 3GS to someone. How to unlock it? i don't have jailbreak. Keep sim card or remove out it before selling. Or must contact AT&T about it???

 

[aziatiklover]

If you are an att customer all your need to do is call them. They will submit a request to apple for an unlock.