Can I unlock my device?

To find out if you can unlock your iPhone or your iPad 3G, open Settings, click on General, then on About and scroll down to Modem Firmware. If the version is equal or below a certain version, it can be software unlocked. Only very old versions of the baseband (Modem Firmware) can be unlocked. If you are running iOS 4.0.2 or older and never upgraded, then there's a good chance you can unlock it. On newer devices you might be able to use a hardware unlock solution or simply buy the unlock from the Carrier.
last edit: 2012-10-09

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