Dev Team have released ultrasn0w 1.0 unlock for iPhone 4. Follow the step by step guide posted below to unlock iPhone 4 (software unlock):
Step 1: Jailbreak iPhone 4 with JailbreakMe. Once Jailbroken, you will find Cydia on HomeScreen.
Step 2: Open Cydia, go to “Manage” tab and tap on “Sources”.
Step 3: Once in “Sources” tap on “Edit” on top-right side, then hit on “Add”. A window will pop up:
Step 4: Enter http://repo666.ultrasn0w.com and hit “Add”.
Step 5: Tap on “Done” on top right corner.
Step 6: Go to “Search” tab in Cydia and search “ultrasn0w”. You should find ultrasn0w in there.
Step 7: Install ultrasn0w (Tap on “Install” on top right corner).
Once installation is complete, your iPhone 4 unlock will complete. Now you can use any sim card on your unlocked iPhone 4.
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