Please note that your device should be on baseband 04.26.08 and running iOS 4 GM build to proceed with unlock using ultrasn0w 0.92.1. If you are on baseband 05.11.07, you can use blacksn0w RC2 to unlock and if you are on baseband 05.12.01, you will have to wait a little longer as Dev-Team is holding the release of unlock tool till iOS 4 public release officially hit the market.
1. Please note that this works on iPhone 3GS only with old bootrom.
2. You iPhone 3GS must be jailbroken on iOS 4 using PwnageTool.
3. Your baseband must be 04.28.06. To check your baseband, route to Settings> General> About> Modem Firmware.
Procedure to unlock iPhone 3GS on iOS 4
- As mentioned in notes, first your iPhone 3GS must be jailbroken on iOS 4 using PwnageTool bundles, step-wise guide is posted here.
- Once you are done with jailbreaking, you can proceed with unlock of your iPhone using ultrasnow
- Start "Cydia" on your iPhone.
- Touch on "Manage" tab on the bottom.
- Now touch on "Sources" as seen in the screenshot below:
- Touch on "Edit" and then on "Add". You will be prompted to enter a url source as seen in the screenshot below. Type "http://ios4.ultrasn0w.org" and touch on "Add Source"
- Cydia will now automatically update your sources by following a series of automated steps
- After installation is completed. Search for "ultrasn0w" in Cydia and install this application. This app will automatically unlock your iPhone so that you can use it with any carrier.
Please try this at your own risk, our recommendation is to wait for official release of iPhone 4.0 OS, which is expected next week.
[update via Redmondpie]
iOS 4 Jailbreak/Unlock Summary
Jailbreak: Apple has released iOS 4 final built/version. iPhone 3G and iPod Touch 2G users can use latest Redsn0w (0.9.5b5-3) for Windows/Mac to jailbreak iOS 4, and iPhone 3GS users can use PwnageTool Bundles to jailbreak iOS 4. GeoHot has also claimed to jailbreak OS 4.0 with Blackra1n tool, but tool hasn't arrived yet.
Unlock: As promised, after public release of iOS 4.0, Dev-Team has released Ultrasn0w 0.93 to unlock iPhone 3G/3GS running latest iOS 4 with baseband 04.26.08, 05.11.07, 05.12.01 and latest 05.13.04. Previously, Dev-Team released Ultrasn0w 0.92.1 to unlock iPhone 3G/3GS with baseband 04.26.08. iPhone 3GS users may also use Blacksn0w RC2 for unlock, but it's not an official tool and bit buggy as well.Contact Us for News Tips, Corrections and Feedback