Talk about fast work, Apple released the final build of iOS 4.2.1 for all iOS devices on 22nd November and a day is all it took for iPhone Dev Team to jailbreak it. They have just announced redsn0w 0.9.6b4 which jailbreaks iOS 4.2.1 on iPhone 4, iPhone 3GS, iPad & iPod touch 4G.
Sadly the jailbreak is not for those Iphones which rely on a carrier unlock with ultrasnow. So stay away if you are using ultrasnow but if you iPhone is factory unlocked than you are good to go.
The Redsnow jailbreaks up until now have been permanent, the jailbroken devices remained jailbroken until a software update or restore. For iOS 4.2.1 the case is different, jailbroken iPhone, iPad or iPod when rebooted, will need to be booted in a “jailbroken state”. This is called a thetered jailbreak and until now it’s the only available jailbreak for iOS 4.2.1.
However the older Apple devices (Iphone 3G, Iphone 3GS oldbootroom and Ipod touch 2G) can still be jailbroken un-thetered using redsnow 0.9.6b4. The rest of the devices (iPhone 3GS new bootrom, iPhone 4, iPadiPod Touch 3G and iPod Touch 4G) can only be jailbroken thetered.
Follow the tutorial below to jailbreak your iPhone 4 3GS 3G, iPad or iPod Touch running iOS 4.2.1 using Redsn0w.
- Download iOS4.2.1 for your device.
- Restore your iDevice to iOS 4.2.1 using iTunes
- Download Redsnow 0.9.6b4 for Windows/Mac.
- Run Redsnow 0.9.6b4 and choose your desired firmware ( iOS 4.2.1 for your device)
- Select “Install Cydia” and any option you might want.
- Turn off your iDevice and connect it to your computer via USB and click NEXT
- Follow the instructions prompted by Redsnow 0.9.6b4 to enter DFU mode.
- Let Redsnow work its magic. When the process will be finished your device will restart and you’ll be able to enjoy your jailbroken iOS 4.2.1