Jailbreak iPhone 4 with RedSn0w 0.9.7 B4 is fairly easy with the USBMUX Process being eliminated in the latest beta release .The current version of the jailbreak tool works on Mac systems only while the Windows version is still under development.
Note that you need iOS 4.2 b3 ipsw files to proceed with the untethered jailbreak , which is currently available only to developers .
Upgrade to iOS 4.2.1 and Jailbreak Tethered :
Step A : To jailbreak your iphone 4 un-tethered , you need to upgrade the iOS of your device [iphone 4 , ipod touch 4 and ipad] to iOS 4.2.1 using iTunes [Download iOS 4.2.1 ipsw – Direct Links] . Follow the upgrade process here [iOS 4.2.1 Upgrade Preserving Baseband] for those who want to retain their unlock [not required for factory unlocked phones].
Step B : After having upgraded to iOS 4.2.1 you need to jailbreak your iphone 4 tethered with RedSn0w 0.9.6 b6 which includes the battery drain fix . Follow the iOS 4.2.1 Tethered RedSn0w Jailbreak tutorial for the step-by-step process . If you have already jailbroken skip the above process .
Un-Tethered Jailbreak iOS 4.2.1 with RedSn0w 0.9.7 b4 :
- Download and run Redsn0w 0.9.7 b4 on your Mac
- Now browse it to iOS 4.2.1 ipsw file downloaded in Step A above . It should be located at “~/Library/iTunes/iPhone Software” Updates by default . Proceed next .
- In the next screen you will be given several options , Select “Install Cydia” and “Jailbreak Monte (untether)” .
- Now choose the iOS 4.2 b3 ipsw firmware file in the next screen. [Download 4.2.1 ipsw on your desktop and select it]
- Follow on-screen instructions to turn off your device and run into DFU Mode . Let the jailbreak process begin and wait till its completed .
If you are having any issues in following the above tutorial , please ask your questions in the comment box below. For other jailbreak problems , use the Jailbreak Forum to post your questions . For more updates , Subscribe to our Email List and Follow us on Facebook.