Thousands of iPhone owners have joined forces with a team of hackers to help them find new ways to jailbreak Apple's phone software.
Jailbreaking involves unlocking a device so that it is not restricted to running software officially approved by the manufacturer.

Mobile phones that run Google's Android operating system do not face this restriction and Microsoft allows its Windows Phone 7 operating system to be unlocked. But Apple has always fought very hard to prevent anyone jailbreaking its devices.

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