The newly released Sn0wbreeze 2.4 supports Ultrasn0w unlock for iPhone 4 and 3GS users (old basebands only) which otherwise happens to be broken on the latest iOS 4.3.1 firmware.
Good news for unlockers! A new version of Sn0wbreeze 2.3 is now available which supports Ultrasn0w unlock for iPhone 4 and 3GS users (old basebands only) running the latest iOS 4.3 firmware.
Its been a while since we last heard or read anything on the upcoming iPhone 4 unlock for 3.10.01 and 2.10.04 basebands. MuscleNerd of iPhone Dev-Team has already confirmed that unlock for iPhone 4 on newer basebands wont be released until Apple drops iOS 4.3 to public.
The following instructions will help iPhone 4 unlockers to update to iOS 4.2.1 while keeping the old 1.59.00 baseband, jailbreak it untethered with GreenPois0n RC5, and then unlock it with Ultrasn0w.
iPhone developer and hacker Sam Bingner has released Subscriber Artificial Module (SAM) method which will allow you to officially activate your iPhone 4, 3GS and 3G without hacktivating, or using original SIM card.
The iPhone Dev-Team has released the updated version of carrier unlocking tool called Ultrasn0w which can unlock the latest iOS 4.2.1 and 4.1 firmware on iPhone 3GS and 3G on basebands later than 05.13.04. Since iPhone 4 has different baseband OS, It'll take a little while longer for the Dev Team to unlock it on the latest firmware.
In a reply to one of his many followers on Twitter, MuscleNerd of iPhone Dev Team has confirmed that ultrasn0w unlock for iPhone 3GS and iPhone 3G on iOS 4.1 and iOS 4.2, with 05.14.02 baseband will be released in a day or two at most, once iOS 4.2 is released to public.
The newly released iOS 4.1 for iPhone 4, 3GS, and 3G features new baseband which is currently not unlockable using the current version of ultrasn0w. But if you upgrade (while preserving baseband) and then jailbreak iPhone 3GS on iOS 4.1 using PwnageTool method posted here, you can unlock your phone (iPhone 3GS) using the existing version of ultrasn0w. Also, if you upgrade your iPhone 4 (while preserving baseband) on iOS 4.1 using the method posted here, you will be able to unlock your phone (iPhone 4) as soon as the new jailbreak tool is available for download.
MiTime app for iPhone 4 has been released which fixes and / or activates FaceTime on unlocked iPhone 4s which are running on unofficial unsupported carriers such as T-Mobile US. According to the description of the app, it should work on just about any carrier worldwide. You must be able to receive an international SMS message to get FaceTime activated via MiTime.