Download Ultrasn0w 1.2.8 To Unlock iPhone 4, iPhone 3GS. 3G On iOS 6.1

Ultrasn0w 1.2.8 is recently released now brings support of iOS 6.1 unlock utility. As for device models supported by this release is iPhone 4 and iPhone 3GS and 3G with specific basebands which I list in this post.
Unlocking iPhone is another joyful thing we should do beside jailbreaking it. We will be able to use any SIMCard or Carrier as we regard have cheaper offers, compared with the locked carrier price.
That’s what Ultrasn0w offers for unlockers, by the way the Ultrasn0w 1.2.8 does support iPhone 4, 3GS, 3G with older basebands therefore don’t update your baseband albeit you update to iOS 6.1, it’s recommended to use a tool like Redsn0w when updating, by going to Extras > Even More > Restore, then don’t select upgrade BB.
Here is a list of basebands and the iOS models supported by Ultrasn0w 1.2.8.

• iPhone 4 baseband 01.59.00
• iPhone 3GS baseband 05.11.07
• iPhone 3GS baseband 05.12.01
• iPhone 3GS baseband 05.13.04
• iPhone 3GS baseband 04.26.08
• iPhone 3GS baseband 06.15.00

You don’t know what’s your baseband version is? Then navigate to Settings > General > About > Modem Firmware.
If yours is included in the list above, then you can launch Cydia to grab Ultrasn0w 1.2.8!