In 2005, when Steve Jobs began planning the iPhone, he had a choice to either "shrink the Mac, which would be an epic feat of engineering, or enlarge the iPod". Jobs favored the former approach but pitted the Macintosh and iPod teams, led by Scott Forstall and Tony Fadell, respectively, against each other in an internal competition, with Forstall winning by creating the iPhone OS. The decision enabled the success of the iPhone as a platform for third-party developers: using a well-known desktop operating system as its basis allowed the many third-party Mac developers to write software for the iPhone with minimal retraining. Forstall was also responsible for creating a software development kit for programmers to build iPhone apps, as well as an App Store within iTunes.
The operating system was unveiled with the iPhone at the Macworld Conference & Expo on January 9, 2007, and released in June of that year. At the time of its unveiling in January, Steve Jobs claimed: "iPhone runs OS X" and runs "desktop-class applications", but at the time of the iPhone's release, the operating system was renamed "iPhone OS". Initially, third-party native applications were not supported. Jobs' reasoning was that developers could build web applications through the Safari web browser that "would behave like native apps on the iPhone".
In September 2007, Apple announced the iPod Touch, a redesigned iPod based on the iPhone form factor and operating system.
In October 2007, Apple announced that a native Software Development Kit (SDK) was under development and that they planned to put it "in developers' hands in February".
On March 6, 2008, Apple held a press event, announcing the iPhone SDK.
The iOS App Store was opened on July 10, 2008, with an initial 500 applications available.
In January 2010, Apple announced the iPad, featuring a larger screen than the iPhone and iPod Touch, and designed for web browsing, media consumption, and reading using the iOS.
Siri is an intelligent personal assistant integrated into iOS. The assistant uses voice queries and a natural language user interface to answer questions, make recommendations, and perform actions by delegating requests to a set of Internet services. The software adapts to users' individual language usages, searches, and preferences, with continuing use. Returned results are individualized. Originally released as an app for iOS in February 2010
In June 2010, Apple rebranded iPhone OS as "iOS". The trademark "IOS" had been used by Cisco for over a decade for its operating system, IOS, used on its routers. To avoid any potential lawsuit, Apple licensed the "IOS" trademark from Cisco.
it was acquired by Apple two months later and then integrated into iPhone 4S at its release in October 2011. At that time, the separate app was also removed from the iOS App Store.
In October 2016, Apple opened its first iOS Developer Academy in Naples inside the University of Naples Federico II's new campus.
The latest version is iOS 13, released on September 19, 2019. It is available for iPhone 6S and later, and the seventh-generation iPod Touch. Alongside iOS 13, Apple debuted iPadOS 13 at its annual WWDC keynote on June 4, 2019. It was released on September 24, 2019. iPadOS is available on iPad Air 2 and later, iPad fifth-generation and later, iPad mini 4 and later and all versions of the iPad Pro.
It was recorded by December 2019, that iOS's market share was 24.79%, while it's competitor Android's market share was 74.13%.
The apps on the AppStore have collectively been downloaded more than 130 billion times. App intelligence firm Sensor Tower has estimated that the App Store will reach 5 million apps by the year 2020.