This is a guide to unlock iPhone 3GS on OS 3.0 with UltraSn0w tool. Before starting the process of unlock iPhone 3GS, your iPhone must be jailbroken but if it is not then fist jailbreak it. Here are the guides available to jailbreak iPhone 3GS with RedSn0w: How to Jailbreak iPhone 3GS OS 3.0 with [...]