iH8sn0w’s Sn0wbreeze 2.3 beta 1 is now available to jailbreak iPhone 4 4.3 iOS and jailbreak iPhone 3GS 4.3 iOS. Sn0wbreeze 2.3 also lets you update to iOS 4.3 without upgrading your baseband. It’s tethered jailbreak at the moment and you will need a tool like iBooty to boot tethered. Here’s the Sn0wbreeze 2.3 tutorial:
How to Jailbreak iPhone 3GS, iPhone 4 4.3 iOS
What you need:
- Sn0wbreeze 2.3 Beta 1 for Windows 7, Vista & XP: sn0wbreeze-2.3b1.zip
- Download Apple iOS 4.3 IPSW for your device
- Download and install Apple iTunes 10.2.1
For convenience, keep all the downloaded files at same place.
Step 1: Extract the sn0wbreeze.zip and launch the sn0wbreeze-2.3b1.exe and click on Next button.

Step 2: Browse for iOS 4.3 IPSW and select it.

Sn0wbreeze will now identify the IPSW. Once it does, click Next button. For iPhone 3GS, it will ask if your device is New Bootrom or Old Bootrom.

Step 3: Select the mode you want to start sn0wbreeze in and click Next.

Simple mode is recommended for common users with factory unlocked iPhone. Baseband Preservation Mode is for those who want to update the iOS without upgrading the basbenad.
Step 4: Sn0wbreeze will ask if you wanted to hacktivate iPhone. Click yes if you’re on unofficial carrier, click no otherwise.
Step 5: Sn0wbreeze will now start the process to jailbreak iOS 4.3 IPSW.

Step 6: Once jailbreak process completes, sn0wbreeze place the jailbroken iOS 4.3 IPSW along with the iBooty-4.3 folder on your desktop and will display the Done message. Click OK.

Sn0wbreeze DFU Pwner will start now. It will show you onscreen instructions to put iPhone in DFU mode.
Step 7: Switch your device off and connect it to the PC. Then click Start button.

Step 8: Now follow the onscreen instructions to get into DFU mode.

Step 9: Once in DFU mode, start iTunes to load custom IPSW.
- iTunes will display a message saying “iTunes has detected an iPhone in recovery mode. You must restore this iPhone before it can be used with iTunes.”, click OK.

- You’ll see the “Restore” button in iTunes.

- Press and hold Shift key (Windows) or Alt key (for Mac) and click on “Restore” button.
- Browse for the custom IPSW that you created using Sn0wbreeze (on your desktop).

- iTunes will now confirm if you wanted to restore to the selected IPSW, click “Restore”.

Step 10: Boot Tethered with iBooty
Once iPhone restore to custom iOS 4.3 firmware IPSW, you will have to boot tethered with iBooty. To do this:
- Open the directory iBooty-for-4.3 placed on your desktop.
- Run the iBooty.exe to start iBooty.

- Click Start and follow the onscreen instructions to boot tethered.
Phew! That’s it. Finally you can run Cydia from Springboard and start the fun!