Earlier today, the iPhone Dev Team released ultrasn0w 1.2.3 to unlock iPhone 4 and iPhone 3GS on iOS 4.3.3. Please remember that ultrasn0w 1.2.3 is not a new unlock and will not work on higher basebands like 02.10.04, 03.10.01, 04.10.01, 05.14.02 and 05.15.04. Ultrasn0w 1.2.3 will only unlock jailbroken iPhone 4 and iPhone 3GS having basebands 01.59.00, 04.26.08, 05.11.07, 05.12.01, 05.13.04 and 06.15.00.
Remember: If you’ve an iPhone 3GS, you first need to update its baseband to iPad baseband 6.15.00. Ultrasn0w unlock requires that your iPhone 3GS is jailbroken with baseband 6.15.00 before ultrasn0w unlock can work. Please keep in mind that updating to iPad baseband 6.15.00 might cause your device to lose GPS functionality.
Step 1: Jailbreak your device.
- How to jailbreak iOS 4.3.3 untethered on iPhone, iPad and iPod touch using Sn0wbreeze 2.7. (unlockable baseband preserved)
- How to jailbreak iOS 4.3.3 untethered on iPhone, iPad and iPod touch using PwnageTool 4.3.3. (unlockable baseband preserved)
- How to jailbreak iOS 4.3.3 untethered on iPhone, iPad and iPod touch using Redsn0w 0.9.6rc15. (unlockable baseband not preserved – not recommended for carrier unlock relying iPhone users)
Step 2: Once your device is successfully jailbroken on iOS 4.3.3, launch Cydia. In the bottom right corner, tap Manage followed by Sources.
Then tap on Edit followed by Add. Cydia will now ask you to enter a URL source. Add:
http://repo666.ultrasn0w.com
and tap on Add Source. Cydia will now automatically add the repository after a couple of automated steps.
Once installation has successfully completed, search for Ultrasn0w 1.2.3 in Cydia. Install it and now you can unlock your iPhone 4, iPhone 3GS to work with any carrier around the world, provided that you’ve preserved the unlockable baseband.
Step 3: Simply restart your iPhone 4 or 3GS and it will now be fully unlocked on compatible basebands, on iOS 4.3.3.