IOS



"There's an app for that."

Apple's iOS (formerly "iPhone OS") is the operating system that powers their iPhones, iPads. It is derived from OS X, but applications are not compatible between the two, and no emulators capable of running commercial apps have been released yet. iOS is much more locked down than rival Android, and its app store is much more restrictive (no controversial or adult content, emulators, non-WebKit browsers, or GPL-licensed applications). Through a process called jailbreaking, you can bypass all of these restrictions (and void your warranty) to use iOS more flexibly; however, Apple keeps trying to stamp it out, so it gets more and more difficult with every new version.