User interface on iOS 10.

iOS (formerly iPhone OS) is an operating system designed for smartphones created and developed by Apple Inc. It is the operating system that presently powers many of the company's mobile devices. It is the second most popular mobile operating system globally after Android. iPad tablets are also the second most popular, by sales, against Android since 2013.

Originally unveiled in 2007, iOS has been extended to support other Apple devices such as iPods and iPads. As of January 2017, the App Store contains more than 2.2 million iOS applications, 725,000 of which are built for iPads. These apps have collectively been downloaded more than 130 billion times.

The iOS operating system is based upon using gestures. Interface control elements consist of sliders, switches, and buttons. Interaction with the OS includes gestures such as swiping, tapping, pinching, and reverse-pinching, all of which have specific definitions within the context of the iOS operating system and its multi-touch interface. Internal are used by some applications to respond to shaking the device (one common result is the command) or rotating it in (one common result is switching between portrait and landscape mode).

Major versions of iOS are released annually. In general, iOS devices are more expensive than Android devices. iOS has been known to have less malware than Android, but this is due to the wall-garden approach of Apple. Apple released their latest version, iOS 12, on September 17th 2018.

iOS is less likely to get viruses, but if people visit malware-injected websites or websites that automatically download iOS zero-day-attacks, then it can still get one, iOS can still have apps uploaded with Xcode and Swift, but is most likely hard. However, jailbroken iOS devices can get malware rather easily due to lack of protection.

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