iOS (formerly
iPhone OS) is a
mobile operating system created and developed by
Apple Inc. exclusively for
its hardware. It is the operating system that presently powers many of the company's mobile devices, including the
iPhone,
iPad, and
iPod touch. It is the second most popular mobile operating system globally after
Android by sales. iPad tablets are also the second most popular, by sales, against Android since 2013, when Android tablet sales increased by 127%.
[6]
Originally unveiled in 2007 for the
iPhone, it has been extended to support other Apple devices such as the
iPod Touch (September 2007) and the
iPad (January 2010). As of June 2016, Apple's
App Store contained more than 2 million iOS applications,
[7] 725,000 of which are native for iPads.
[8]These
mobile apps have collectively been downloaded more than 130 billion times.
[7]
The iOS
user interface is based upon
direct manipulation, using
multi-touch gestures. Interface control elements consist of sliders, switches, and buttons. Interaction with the OS includes gestures such as
swipe,
tap,
pinch, and
reverse pinch, all of which have specific definitions within the context of the iOS operating system and its multi-touch interface. Internal
accelerometers are used by some applications to respond to shaking the device (one common result is the
undo command) or rotating it in
three dimensions (one common result is switching between portrait and landscape mode).
Major versions of iOS are released annually. The current version,
iOS 10, was released on September 13, 2016.
[9] It runs on the
iPhone 5 and later,
iPad (4th generation) and later,
iPad Pro,
iPad Mini 2 and later, and the
6th-generation iPod Touch. In iOS, there are four
abstraction layers: the Core OS,
Core Services, Media, and Cocoa Touch layers. iOS 10 dedicates around 1.8GB of the device's flash memory for itself.
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