History of iPhone
On January 9, 2007, Steve Jobs announced iPhone at the Macworld convention, receiving substantial media attention. Jobs announced that the first iPhone would be released later that year. On June 29, 2007, the first iPhone was released.
IPhone OS 1
iPhone OS 1 is the first major release of iOS, Apple's mobile operating system. iPhone OS 1.1.5 is the latest and the last version of Apple's iPhone OS 1. This version of iOS was the first iteration of the touch-centric mobile operating system. No official name was given on its initial release; Apple marketing literature simply stated that the iPhone runs a version of Apple's desktop operating system, macOS, then known as Mac OS X. On March 6, 2008, with the release of the iPhone software development kit (iPhone SDK), Apple named it "iPhone OS" (they later went on to rename it "iOS" on June 7, 2010). It was succeeded by iPhone OS 2 on July 11, 2008.