THIS JAILBREAKS iPhone 4, 3GS, 3G, iPod touch 4G, 3G, 2G and iPad. Running iOS 3.1.3 to 4.2.1.

First of all so you know this is a tethered jailbreak which means EVERYTIME you reboot your iDevice you have to basically re-jailbreak but its not as hard as you think.. I will tell you how to do this when we get there.

Step 1. Go to the these Websites...
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This is for iOS that you will use for this jailbreak. Just find your iDevice, Generation, and the 4.2.1 or 4.2 IPSW (iOS). Be sure To SAVE this on your DESKTOP.

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PC [ Register or Signin to view external links. ]

This is the steadiest version of Redsn0w to date. Just pick Mac or PC.

Step 2. Open up redsn0w

Step 3. In the Bottom left hand corner it will say browse. click on that and find the IPSW (iOS) you downloaded ( Hopefully you saved it on your desktop). IF the first time it says unable to recognize try again and it should work. Once recognized, click next.

Step 4. It will bring up a window that says "Preparing jailbreak data" or something to that affect. Then It will bring you to another page. FOR A SIMPLE JAILBREAK JUST CLICK ON INSTALL CYDIA (RECOMMENDED). You should also see an option that says " Just boot Tethered right now". We will use that later.

Step 5. It will give you on screen intrustions on how to put your iDevice into DFU mode. Follow them carefully. HOLD POWER BUTTON FOR 3 SECONDS. WITHOUT RELEASING POWER BUTTON HOLD DOWN HOME BUTTON FOR 10 SECONDS. WITHOUT RELEASING HOME BUTTON RELEASE POWER BUTTON AND HOLD FOR 15 SECONDS.After putting it into DFU mode. IT will start the jailbreak. When its done it will give you a warning. PAY CLOSE ATTENTION to the warning. Before you can use cydia you will have to run the iDevice through Redn0w again but this time checking " Just boot tethered right now."

Step 6. ENJOY. BUT DONT FORGET. In cydia after downloading certain things there will be times where you have to " Reboot device" after you reboot it. YOU HAVE TO RUN IT THROUGH Redsn0w AGAIN.

Here is a link to video that shows the basics of How to use Cydia.
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