The beta version of iOS 5 has been jailbroken by the infamous iPhone Dev Team less than a day after its release.
The operating system can be hacked using the 'Limera1n' tool. The jailbreak allows users to install third-party program Cydia and download apps without using the Apple App Store.
IPhone Dev Team member MuscleNerd posted pictures of a fourth-generation iPod Touch running the beta of iOS 5 with Cydia installed.
However, the tethered-boot jailbreak means that devices must be connected to a computer every time they are rebooted.
Apple will officially release iOS 5 in the autumn of 2011, when the company is likely to debut the iPhone 5.
Meanwhile, some Apple users managed to upload iOS 5 onto their devices without the need for a jailbreak. Teenaged developer Mert Erdir emailed full instructions to Gizmodo on how to download iOS 5 via a back door.
The hack involves downloading the IPSW firmware file from the internet and updating the software from within the iTunes 'check for new software' menu. It exploits a flaw in the activation system by using the Voice Over functionality on the iPhone.
Erdir demonstrated how to activate the operating system on an iPhone in a video posted on Gizmodo.
"My will is not to do something harmful to anyone. I just wanted to get the attention of Apple, the company I'm in love with, and maybe one day have a chance to talk to/meet Steve Jobs himself," he said.
However, it appears that Apple has already sealed the backdoor, so those who have not already used the hack are unlikely to be able to do so now.
"I think Apple sent an update over the air to fix my workaround," Erdir tweeted to one of his followers.
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