iPhone 4 Unlock might take long. New Baseband OS will require rewrite of ultrasn0w

That’s right. Unless you got a factory unlocked iPhone 4, which is available almost everywhere except the US right now, you wouldn’t be able to carrier unlock your iPhone 4 for some time to come. While iOS 4 on iPhone 3G and iPhone 3GS has already been unlocked with ultrasn0w 0.93, the baseband OS in iPhone 4 is completely different.pmb9800

iPhone 3G and 3GS have a different baseband CPU than the iPhone 4 hence running different OS as well.

The iPhone 3G and 3G[S] both ran Nucleus OS on thePMB8878 baseband CPU (aka XGold 608), where the iPhone 2G ran the PMB8876 (aka S-Gold 2). iPhone 4 uses the PMB9800, or X-Gold 618 – running a separate OS – ThreadX, an RTOS by ExpressLogic.

Before the unlock, the iPhone 4 needs to be jailbroken as well. Once that’s been done, the work on an unlock will start. Don’t keep your hopes up on getting a locked iPhone 4 and using it with another carrier anytime soon. A safe bet would be to get a factory unlocked version.

Of course, we’ll keep you updated on any progress on this. Stay tuned! [via ModMyi]

About the Author

Imran Hussain is the founder and editor of iThinkDifferent, which he launched in 2008 to cover Apple news, reviews, and how-to guides. He has spent over 15 years writing about iOS, macOS, and the wider Apple ecosystem, with a focus on hands-on guides - installing developer betas, troubleshooting, and walking through new features on his own devices. Based in Dubai, he also loves to cover photography, gaming, and the tech industry more broadly on his social media profiles.

6 comments

  1. Damn, I want to buy an Iphone 4 ASAP, I just had my Unlocked I-phone 3G stolen at Busch Gardens two days ago, and am now forced to use a sidekick since I have T-mobile.

  2. This sucks. I'm itching to get the new phone but I really need the carrier unlock. Not to escape AT&T here, but to use it overseas when I travel a couple of times a year. As if I'm going to pay AT&T or anybody's international roaming! Isn't locking something we own unconstitutional? Is this grounds for a class action lawsuit?

  3. If you're in the US, just take a quick trip up to Canada in a few months and buy an unlocked iPhone in an Apple Store.

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