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.
History of iPhone
During Apple's official unveiling of iPhone 4S on October 4, 2011, it was announced that Sprint would begin carrying the reconfigured CDMA iPhone 4 and iPhone 4S in the US on October 14. Cricket Wireless announced on May 31, 2012 that it would become the first prepaid carrier in the US to offer iPhone 4 and iPhone 4S, beginning June 22, 2012. A week later, Virgin Mobile USA became the second American prepaid carrier to offer iPhone 4 and 4S, announcing plans to release the phones on June 29, 2012. T-Mobile began offering iPhone on April 12, 2013.