This document summarizes the history and evolution of the iOS mobile operating system from its initial release in 2007 through 2012. It details each major iOS release, the devices it was compatible with, and the new features introduced, such as the App Store, multitasking, Siri, and iCloud. Key developments include the launch of the iPhone and iPod Touch, the introduction of third-party apps and the App Store, and the integration of services like FaceTime, iMessage, Maps, and Passbook. The iOS operating system was initially developed by Apple for their mobile devices.