iOS has followed more or less the same design blueprint since its introduction in 2007, albeit with refinements along the way. But what we see in iOS 7 is nothing less than a full-fledged overhaul of the operating system's look and feel, while maintaining the interface that makes the device so easy to use.

From the lock screen to the Settings app, almost nothing has gone untouched visually in iOS 7. Apple has banished skeuomorphism. Instead, we get a straightforward, lightweight interface with an emphasis on thin, space-saving text and high contrast.

Gone, for the most part, are richly textured icons; in are simple schematic-like designs with little shading and depth. Likewise, either text or icons have replaced buttons in most places. The remaining buttons are generally very simple – for instance, a circular border with text in it.

Whether you love or hate the new design – or fall somewhere in between – it's going to require an adjustment.