During release, the iPhone was marketed as running "OS X". The name of the operating system was revealed in the iPhone 2.0 SDK. Apple has released 4 major software versions for the iPhone, including the one bundled with original iPhone units.

Currently, software updates for the iPhone have been discontinued. However, unlicensed third-parties are known for creating custom firmwares for the iPhone, as well as hacking Android OS onto the iPhone.

[edit]Software History

The original release of the operating system included Visual Voicemail, multi-touch gestures, HTML email, Safari web browser, threaded text messaging, and YouTube. However, many features like MMS, third-party apps, and copy and paste were not supported at release. These missing features led to hackers "jailbreaking" their phones which added these missing features. Official software updates slowly added these features.

iPhone OS 2.0 (released July 11, 2008) introduced 3rd party applications, exchange support, push e-mail, and other enhancements.

iPhone OS 3.0 (released June 17, 2009) introduced copy and paste, and new YouTube features. Not all of the features of iPhone OS 3.0 were supported on the original iPhone.

The original iPhone did not receive the iOS 4 software upgrade, due to hardware constraints.


Unlicensed third party software and jailbreaking

The iPhone's operating system is designed to only run software that has an Apple-approved cryptographic signature. This restriction can be overcome by "jailbreaking" the phone,[30] which involves replacing the iPhone's firmware with a slightly modified version that does not enforce the signature check. Doing so may be a circumvention of Apple's technical protection measures.[31] Apple, in a statement to the United States Copyright Office in response to EFF lobbying for a DMCA exception for this kind of hacking, claimed that jailbreaking the iPhone would be copyright infringement due to the necessary modification of system software.[32] Jailbroken iPhones may be susceptible to computer viruses, but few such incidents have been reported.[33][34] Recently, the U.S Copyright Office has said that they are not going to prosecute jailbreakers.[35]