IOS 2

iOS is a mobile operating system, developed by Apple Inc. for iPhone, iPad, and iPod touch. Updates for iOS are released through the iTunes software, and, since iOS 5, via over-the-air software updates. With the announcement of iOS 5.0 on June 6, 2011, a USB connection to iTunes was no longer needed to activate iOS devices; data synchronization can happen automatically and wirelessly through Apple's iCloud service. Major new iOS releases are announced yearly during the Apple Worldwide Developers Conference (WWDC), and are usually released in September of the same year, usually coinciding with the release of new iPhone models. The most recent stable release, iOS 10.2.1, was released on January 23, 2017, and the most recent beta release, iOS 10.3 Beta 7, was released on March 16, 2017.

iOS did not have an official name until the official release of the iPhone software development kit (iPhone SDK) on March 6, 2008. Before then, Apple marketing simply stated that iPhone ran a version of Mac OS X made specifically for iPhone. When iOS was introduced, it was named iPhone OS. It was officially renamed iOS on June 7, 2010 with the announcement and introduction of iPad. The introduction of iPad, and the existence of iPod touch, meant the iPhone was no longer the only device to run the mobile operating system. iOS 4 was the first major iOS release that reflected the name change. Apple licensed the "iOS" trademark from Cisco Systems.

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June 2007 saw the official first version release of what eventually became iOS – concurrently with the first iPhone. The final 1.x series release was 1.1.5, released shortly after iPhone OS 2.0.

July 11, 2008 saw the public release of iPhone OS 2.0, with upgrades through version 2.2.1 made available.

iPhone OS 3.0 was officially released on June 17, 2009 for iPhone and iPod touch. iPhone OS 3 had updates until version 3.1.3 (released on February 2, 2010). The first generation iPod touch and iPhone have iPhone OS 3.1.3 as their newest available version. iOS 3.2.x was made specifically for the iPad.

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