Dieter Bohn of The Verge has an amazing walkthrough of how iOS has evolved since its release in 2007. The post takes a detailed look at the key iOS features and releases that Apple introduced throughout the years.
During the original iPhone announcement, Apple touted that it ran on the same Unix core as Mac OS X and that it used many of the same tools. However, it was clear even then that while there may be some shared elements between OS X and this new phone OS, it was a different-enough beast to warrant its own branding. When the original iPhone launched, the OS was called “iPhone OS” and it kept that name for four years, only changing to iOS with the release of iOS 4 in June of 2010. For the sake of simplicity (and because it’s a much-less awkward phrase), I’m going to indulge in a little revisionist history here and refer to all versions of the operating system as “iOS” in this piece.
Head on over to The Verge to read about the history of iOS. It’s amazing to see how far the platform has come.