Jailbreaking is the name of  a process that will allow the  persons that use iPhone and iPod Touch to run codes that don’t have the official Apple’s authorization, and that are not downloaded from the App Store. After the complete jailbroken process, iPhone users can  download a lot of applications and programs that couldn’t work before on their devices because they didn’t had the Apple’s unique signature. There is some unofficial installers software like Cydia, Rock App, Icy, or Installer. Cydia is the most used program, while Rock App features a small catalog full with paid applications. Icy and Installer are very rarely used and are unsupported even by their developers. The person who founded Cydia, Jay Freeman, made the approximate estimation of this business and found that   that over 4 million from the totally of 40 million units of iPods and iPhones sold all over the world are jailbroken.

Jailbreaking is not the same with the SIM unlocking, that  is the process by which a mobile device is become compatible with the networks that aren’t supposed to work on them.

The iPhone OS has been subject to a variety of different hacks for a variety of reasons, centered on adding functionality not supported by Apple.

The iPhone Dev Team is a group of cyberpunks in the iPhone OS community that have released a lot of ingenuous  tools capable to enable the use of applications unauthorized on the iPhone and iPod Touch and to make possible  the use of the iPhone on GSM carriers without official authorization from Apple. These softwares are made to provide to the owners the capacity to avoid the restrictions of devices, letting for activities such as deep custom make and easy roaming. The hackers and their programs became a symbol for this activity that is named jailbreak.

The iPhone Dev Team’s programs have been applied on over 1,6 million devices all over the world and their blog collected hundreds  of commentaries on every post that announce a new release of a software, in only few hours.

With the arrival of the iPhone operating system 2.0, the user’s community has been concentrated over the jailbreak of these devices. Anterior to iPhone 2.0 official release, jailbreaking was the only method to allow 3rd -party programs on the device. Now with iPhone 2.0, original applications are permitted under Apple’s SDK agreement terms, even thought some functionality are prohibited on the iPhones or iPods. From these category of prohibited functions are included and the background applications, or the capability for 3rd -party softwares to run after seeming to have stopped, and the capability to change the applications written for the device by Apple itself. Some started efforts to disable Apple’s kill switch option, even though these efforts were mostly leaved behind once the kill switch was demonstrated that will only disable Core Location.

The other greater concentration of attention to the jailbreaking since the official release of 2.0 operating system, has been to reverse the SIM Lock that is pushed to the most of the iPhone devices. The 1st generation of iPhones can be totally  unlocked with the iPhone Dev Team’s Boot Neuter software, and the iPhone 3G can become unlocked with a new beta attempt named  yellowsn0w initially that become ultrasn0w.

More recently, many attempts have been centered on  extending the Bluetooth capacities of the iPhone. Despite this, many of the actions  stopped due to the preview of the iPhone 3.0 operating system on March 17, 2009, that had, among other features , upgraded the  Bluetooth capabilities.

After some days from the official release of the 3.0 version of this operating system , updated instructions and softwares to jailbreak and unlock 3G iPhones were released by the iPhone Dev Team.

The iPhone Dev Team declared that the softwares that are able to jailbreak the iPod Touch 2G or to unlock the iPhone 3G will also be able to do the same things to the  iPhone 3GS.

On July 3, 2009 Geo Hot made available the purplera1n, a software able to jailbreak an iPhone 3GS that have the 3.0 version of the iPhone OS X implemented. The iPhone Dev Team later brought out an updated version of the redsn0w jailbreak and ultrasn0w unlock for the iPhone 3GS.

Also, the iPhone Dev Team released and an update to their Pwnage Tool program on October 2, 2009, capable of the  jailbreaking of OS 3.1 on the iPhone 3GS devices.

On October 11, 2009, Geo Hot released blackra1n, a software that is able to jailbreak firm ware versions of up to the latest ones, between all other iDevices, the iPhone 3GS and iPod Touch 3rd G. Blackra1n holds even iPhone 3GS which has 3.1.2 installed out- of- the- box.