The release of a new iPhone means two things. The first is obviously the new phone; but that hardware is also accompanied by a new version of iOS. Apple's mobile operating system has evolved from a relatively simple interface for using a few stock Apple apps (on 2007's debut iPhone) to an advanced system that is creeping ever closer to OS X. The annual iOS refresh is now an event in itself. Let's take a look at the decisions – and execution – that Apple ultimately took with this year's update.