Initially priced at US$599 and US$499 for the 8 GB and 4 GB models, the iPhone went on sale on June 29, 2007.
The first jailbreaking method was released on July 10, 2007
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With the July 11, 2008 release of the iPhone 3G
2008
Upon the nearing release of iOS 2.0 (previously iPhone OS), a hacker group called the iPhone Dev Team released a jailbreaking application named PwnageTool that used a graphical user interface.[5] It is capable of creating custom firmwares, from which devices can be restored.
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On March 17, 2009, Apple announced the release of iOS 3.0.[7] Three months later, the iPhone Dev Team released PwnageTool 3.0 and redsn0w 0.7.2, which allowed users of the original iPhone, iPhone 3G, and iPod Touch running the OS 3.0 to be jailbroken on both Macs and PCs.[8]
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On September 9, 2009, Apple released iOS 3.1, again disabling the ability to jailbreak the device. The iPhone Dev Team released PwnageTool 3.1-3 to jailbreak for all devices (except the iPod Touch 3G).[9]
On October 11, 2009, George Hotz, known under the alias Geohot, released the tool blackra1n, which allows the jailbreaking of all iPhones (up to the old 3GS) and iPod touch (up to 3G) devices running iOS 3.1.2 (although the iPod Touch 3G is tethered; it must be plugged into a computer, and blackra1n must be run to boot the device every time it shuts down).
On October 25, 2009 Geohot released a newer version of blackra1n, RC2, an update that was able to tethered jailbreak the new iPhone 3GS the new iPod Touch 2G 8GB MC model. All of the tethered devices feature an updated boot ROM in which Apple had closed the 24kpwn loophole exploited by the iphone and chronic dev teams. Geohot also released "blacksn0w", an unlocking application for the iPhone which was capable of unlocking the newest baseband version, 5.11.07. Released on November 2, 2009, blackra1n RC3 is the current version, which also includes blacksn0w.
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iOS 4.0 was released June 21, 2010