how do you unlock and jail break an iphone from at&t to work for t-mobile?

Of course you can! Unless its an iphone 4th on the latest bb, otherwise its totally unlockable.
It matters which bb and o you are running but the most common one is blackra1n Google blackra1n and/or redsn0w, download it. Follow the steps. It will take you like 5 mins and 4 clicks.
Remember, before doing that, make a backup.

you need to know what software ure running. Go to settings, general, about. scroll down to version and depending on what version you're running. u need to use the appropriate program such as Redsnow, spirit or blackrain.

once jailbroken, use ultrasnow to unlock.

If you need tutorial, search it on youtube, it has videos so you cant mess it up

Good luck!

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