In Pictures: The Apple family tree

iOS (2007 to present)

CPU class: ARM OS: iOS Development status: Moderated Platform size: 16

iOS began is life as iPhone OS, which itself stemmed from Apple’s OS X desktop OS. This touchscreen operating system powers three distinct hardware subplatforms: iPhone, iPod touch, and iPad. Each contains a CPU based on the ARM microprocessor architecture. Many iOS apps can run on all three subplatforms, while others are limited to or optimized for a certain iOS device class.

iOS initially shipped on the 2007 iPhone without the App Store or any means of installing third-party applications. In 2008, Apple launched the App Store, and iOS quickly became one of the most populous software platforms of all time.