Matthew Panzarino, for TNW:
We reported Friday that AT&T was beginning to unlock out-of-contract iPhones as of April 8th, today. Now a few more details of the process are available.
First, you can do this in-store, but you can also do it in an online chat at AT&T’s website. The process is painless and only takes a few minutes in the chat. The only piece of information required by AT&T is the International Mobile Equipment Identity (IMEI) number, which can be found under Settings>General>About on your device.
I will certainly give this a spin with my old 3GS.