This is good news for users who own an iPhone 4/iPad/iPod Touch 4G/iPhone 3GS (with new bootrom) as currently Redsn0w and PwnageTool for iOS 4.2.1 can jailbreak newer iDevices on iOS 4.2.1 but it is tethered. iPhone 3G and iPhone 3GS (older bootrom) users are the lucky ones to enjoy an untethered jailbreak.
MuscleNerd tweeted the news:
Got “backup plan” for untethered 4.2.1 JB working (video coming up). Uses mysterious 4.2b3 hashes Cydia kept for you
(It’s a “backup plan” because comex is working on a more extensible one, but this method is also generalizable)
ipt4g 4.2.1 untethered JB w/4.2b3 kernel: http://is.gd/inE4e … Wastes no exploits, but upcoming @comex JB maybe better
So what does ‘tethered jailbreak’ mean?
Tethered means that the jailbreak needs to be reapplied every time you power down your jailbroken iDevice. If you let the battery run out or restart your iDevice then you will need to reapply the jailbreak by connecting to your computer (tethering).
The only hitch that we see with this method is it needs iOS 4.2 beta 3 SHSH blobs.
He has also published the video of untethered jailbroken iPod touch 4G:
MuscleNerd hasn’t provided an ETA on when the updated tools will be released.
Have you been waiting for a untethered jailbreak for iOS 4.2.1? Do you have iOS 4.2 beta 3 SHSH blobs saved via Cydia. Tell us in the comments section below.