i OS (formerly i Phone OS) is a mobile operating system created and developed by Apple Inc. It is the operating system that presently powers many of the company's mobile devices, including the i Phone, i Pad, and i Pod Touch.
The home screen appears whenever the user unlocks the device or presses the physical "Home" button whilst in another app.Before i OS 4 on the i Phone 3GS (or later), the screen's background could be customized only through jailbreaking, but can now be changed out-of-the-box.It is available for all i OS devices with 64-bit processors; the i Phone 5S and later i Phone models, the i Pad (2017), the i Pad Air and later i Pad Air models, all i Pad Pro models, the i Pad Mini 2 and later i Pad Mini models, and the sixth-generation i Pod Touch.In 2005, when Steve Jobs began planning the i Phone, he had a choice to either "shrink the Mac, which would be an epic feat of engineering, or enlarge the i Pod".This gives a Spotlight endowed with Siri suggestions, which include app suggestions, contact suggestions and news.
Since i OS 3.2, users are able to set a background image for the Home screen.
Originally unveiled in 2007 for the i Phone, i OS has been extended to support other Apple devices such as the i Pod Touch (September 2007) and the i Pad (January 2010).
As of January 2017, Apple's App Store contains more than 2.2 million i OS applications, 1 million of which are native for i Pads.
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 i OS operating system and its multi-touch interface.
Forstall was also responsible for creating a software development kit for programmers to build i Phone apps, as well as an App Store within i Tunes.