You can Jailbreak 4.2.1 iPhone 4 or other models now “untethered” using GreenP0ison.
GreenPois0n is available to jailbreak 4.2.1 iphone untethered on windows and mac osx both.
This iphone 4 4.2.1 jailbreak is untethered and you don’t need to follow steps after every restart of the phone.
These steps work for to jailbreak 4.2.1 iphone untethered on windows as well as to jailbreak 4.2.1 iphone untethered on mac. Only make sure you download the correct version of GreenPois0n for windows or mac osx.
How to Jailbreak iPhone 4 4.2.1 untethered
1. Download GreenPois0n and launch it to jailbreak iphone 4.2.1 untethered
2. connect your iPhone to your computer via USB
3. click “Jailbreak” button on GreenPois0n screen
4. enter DFU mode (by following the on screen instructions on GreenPois0n windows)
5. let GreenPois0n complete untethered jailbreak for iPhone 4.2.1
6. Once jailbreak for iPhone 4 4.2.1 is successfully completed goto iPhone home screen and find “installer”. Use it to install Cydia.(jailbreak looks incomplete without cydia :D )
You’re all done! Your Jailbreak to iPhone 4 4.2.1 – untethered is completed successfully.
Let me know if you have difficulties while trying to jailbreak 4.2.1 iPhone untethered.