(adsbygoogle = window.adsbygoogle || []).push({}); I have an iPhone 3G that's running 4.2.1 which I got from my cousin who swears it's never been jailbroken (which I believe). What would be the best firmware to install on it in order to unlock the carrier through jailbreak as it's currently UK O2 and I want Three, as I understand 4.2.1 included can't be unlocked for other networks.

I suggest to use Whited00r custom firmware. It's the best to use for older devices for speed and efficiency. Plus it comes pre-unlocked

You must login or register to view this content.