Recently, a cracke found an unlock BUG existed in the AT&T GSM iPhone 4S locked version, you can unlock iPhone 4S locked version without UltraSn0w or Gevey SIM such tools, turn a locked iPhone 4S into unlock version. You only need to perform follow these simple steps to let you use locked iPhone 4S on any carrier.

GSM card needs to be cut down to match Mini SIM card size.

The following is Steps:

1. Insert original carrier AT&T SIM card
2. Dial 611 for AT&T customer service hotline and drop the call
3. Turn on Airplane Mode
4. Take out AT&T SIM card
5. Insert T-Mobile SIM card
6. Make sure WiFi is off ( also tap on ‘Forget this Network” to make sure it doesn’t connect automatically later)
7. Switch off Airplane Mode and iPhone will search for network. This is followed by the Apple splash screen appearing.
8. Activation Required will be displayed on the screen
9. EDGE network will activate automatically – notice the ‘E’ on the top left corner of the screen
10. Wait for about 20-30 seconds and turn off the phone
11. Turn on iPhone and the same Activation Required screen will be displayed
12. When you see one signal bar, tap on Use Cellular Connection
13. Eject SIM card
14. Activation Required screen will be displayed the second time
15. Insert SIM card
16. Unlocked!

This method is simple and feasible, but does not support the CDMA ocked version. And now do not know this BUG from the carrier or Apple systems. And Apple’s next upgrade will certainly block the BUG, so now you try to unlock it as soon as possible!