iOS; How to Jailbreak Your iOS 4.2.1 Device

Greenpoison finally bringns untethered jailbreaking to iOS 4.2.1 devices. The process is fairly easy, but there have been a few problems reported since the release so we're going to walk you through a successful jailbreak step-by-step. Learn here. 

Apple iPhone 4 Black Smartphone 16GB (AT&T)