In this guide I will show you how to jailbreak all devices that are running on version 4.2.1.
Step 1. Plug in your device to your computer then turn it off.
Step 2. Open Greenpois0n.
Step 3. Click prepare to jailbreak
step 4. Enter DFU mode by following the instructions on Greenpois0n
Step 5. Click jailbreak
Your device will then reboot. After it reboots you will need to go to the application on your device called loader. Then you can install Cydia.
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