History of Apple Inc.
The first version of the iPhone became publicly available on June 29, 2007 in selected countries/markets. It was another 12 months before the iPhone 3G became available on July 11, 2008. Apple announced the iPhone 3GS on June 8, 2009, along with plans to release it later in June, July, and August, starting with the U.S., Canada and major European countries on June 19. This 12-month iteration cycle has continued with the iPhone 4 model arriving in similar fashion in 2010, a Verizon model was released in February 2011, and a Sprint model in October 2011, shortly after Jobs' death.
IPhone X
Along with the iPhone 6s, its Plus variant, and the iPhone SE, the iPhone X was discontinued on September 12, 2018 following the announcement of the new iPhone XS, iPhone XS Max and iPhone XR devices. As a result, with a shelf life of just over 10 months, the iPhone X had the shortest ever tenure as the flagship device in the history of the iPhone.