The iPhone Team has released update of RedSn0w 0.9.8 b3 to jailbreak iPhone 4, 3GS, iPod Touch 4, 3G and iPad 1 on iOS 4.3.4 which is a tethered jailbreak.
It is already known that iOS 4.3.4 update does not include any new features and only fixes the exploit which has been used by JailbreakMe 3.0, so it is not necessary to upgrade to iOS 4.3.4 as its jailbreak is only tethered at the moment.
How to Jailbreak iPhone 4, 3GS iOS 4.3.4 with RedSn0w
Step 1
Step 2
Restore iOS 4.3.4 on your iDevice if that’s not running over iOS 4.3.4
Step 3
Run Redsn0w, click on Browse button to select the download iOS 4.3.4 firmware file and let it recognize your IPSW and then click on Next
Step 4
Check mark the box followed by Install Cydia and click Next
Step 5
Make it sure that your iDevice is Turned OFF and Plugged in to your system and then click Next
Step 6
Follow the on screen instructions to put your iDevice into DFU Mode
Step 7
When your iDevice will get enter into DFU mode successfully, RedSn0w will start tethered jailbreaking process
On completion you will have your jailbroken iDevice over iOS 4.3.4
Tether Boot
Step-1
Run Redsn0w and point it to IPSW file
Step-2
Select Just boot tethered right now option and go next
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