Apple's iOS may be undergoing the biggest change since its inception, but that doesn't mean the spirit of the operating system hasn't been floating around designer's heads for hundreds of years. In 1525, before the iPhone was even a twinkle in Steve Jobs' eye, German polymath Albrecht Dürer was espousing similar design principles using the same, now-infamous letters: I, O and S.
Of course, Dürer wasn't referring to an operating system, and (barring any unknown DeLorean use) almost certainly wouldn't have been able to fathom the concept of an OS. In his Introduction to Measurement though, Dürer did explain how artists and designers could create three-dimensional illusions based on what he called "IOS". Except he was referring to the shape of the letters, not the semantics.
Now, the fact that these three vital shapes also happen to form the letters of Apple's mobile operating system is a fun little coincidence. But there is a more substantial link here, in the fact that both use the most basic elements of design to create a realistic, dynamic experience out of something inherently lifeless. Albrecht was known for his high-quality woodcuts and exquisitely lifelike prints, all of which employed his "IOS" rules to convey a sense of realism.
Similarly, iOS was initially praised for the skeuomorphism that gave the masses the ability to grasp an entirely new way of interacting with a phone. Now the real question is — would Dürer be able to get behind flat design? [The Getty]