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Download iFaith: http://ih8sn0w.com/index.php/products/view/ifaith.snow
More jailbreaking info: http://stateofjailbreak.com
iFaith: Save SHSH Blobs on Any Firmware
In this video I give a full tutorial on how to use iFaith by iH8sn0w. iFaith allows you to save SHSH blobs from the iPhone 3GS, iPhone 4, iPod touch 3G, iPod touch 4G, iPad 1 and Apple TV 2 to be saved locally on your computer as well as online. What makes iFaith special is that it allows you to save the SHSH blobs from any firmware from 3.1.x all the way to the most recent 4.3.3 release of iOS as long as you are still on that firmware. So if you are on a previous version of iOS such as 4.0.1 and need to keep your unlock you can use iFaith to save your SHSH blobs and then restore back to your current firmware whenever you want.