How to Jailbreak iOS 4.2.1 Device / Verizon iPhone Using Greenpois0n [Jailbreak Superguide]



Chronic Dev has released its Mac version of greenpois0n, a 1-click jailbreak solution (see why you should jailbreak here). However, it will NOT unlock the device, enabling it to be used with different GSM carriers worldwide.

It is pretty easy to use and worked perfectly with my iPhone 4. Besides the tool, there’s a ‘Loader’ application that gets automatically installed on the iPhone after jailbreak, which gives you option to install Cydia.

Here’s how it works.


  • An iPhone (3GS or later) / iPod Touch (G3 or later) / iPad
  • iOS 4.2.1 / iOS 4.2.6
  • greenpois0n RC5 b4 tool available at or here.
  • iTunes 10.1 or later
  • A wireless internet connection (to install cydia)

Now, let’s get started with the procedure:

1. Download the greenpois0n tool. Double-click the zip file to extract the greenpois0n application and open it.

2. Make sure your iPhone / iPod Touch / iPad is attached to the Mac and click ‘Jailbreak’. NOTE: This will NOT unlock your iPhone (enabling it to be used with other carriers).

3. Greenpois0n will now give you 5 seconds to get ready. It will now ask you to ‘Press and hold the sleep button.’ for 3 seconds and then ‘Continue holding sleep; press and hold home.’ for 10 seconds. After this, it will finally tell you to ‘Release sleep button; continue holding home.’ for another 10 seconds.

4. Now, it begins ‘jaibreaking’ the device and a few seconds later,  greenpois0n displays success message, click ‘Complete!’ to quit the application. Some code will scroll on the screen of your device and it will then reboot.

5. When the device reboots, make sure you have an active internet connection on it.

6. Navigate to the last page of the device’s springboard and open the Loader app.

7. Now select Cydia and tap on ‘Install Cydia’ button that pops up. It will now download Cydia. Once done, it will ask if you want to remove the loader app, you can choose ‘Remove’, if you want to and then the device will re-spring (refresh).

8. After the device re-springs, you will have Cydia installed. Congratulations! Your iOS device is now successfully jailbroken.

All the credit for the great tool goes to Chronic Dev.


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