GreenPois0n jailbreaking tool was developed by Chronic dev team. It can be used to untethered jailbreak iPhone, iPad, iPod Touch or Apple Tv 2G. It is available for Windows and Mac. It can only jailbreak iOs devices upto iOS 4.2.1. Following devices are supported:
  • iPhone 3G, iPhone 3GS, iPhone 4
  • iPod Touch 2G, iPod Touch 3G, iPod Touch 4G
  • iPad 1st Generation
  • Apple TV 2G

Download required Greenpois0n software from links belo, plug your device into your computer and run greenpois0n. Click Jailbreak and follow the on-screen insturctions to put your device into dfu mode and start the jailbreaking process. After a few minutes, greenpois0n will display a ‘Complete’ message. Your device will now reboot and after that locate ‘Loader’ icon on your device and run it. This action will download the Cydia app and install it for you.

Greenpois0n download links:

For iOS 4.2.1: GreenPois0n RC6.1
Windows – Download 

 Mac OS X – Download

For iOS 4.1: GreenPois0n RC4
Windows – Download
Mac OS X – Download
Linux (RC3.3) – Download

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