SAN FRANCISCO (AP) — Apple is throwing out most of the real-world graphical cues from its iPhone and iPad software, like the casino-green "felt" of its Game Center app, in what it calls the biggest update since the iPhone's launch in 2007.

The new operating system, called iOS 7, strives for a clean, simple, translucent look. Apple is redesigning all its applications and icons to conform to the new look, driven by long-time hardware design head Jony Ive.

Apple demonstrated the new software at the Worldwide Developers Conference in San Francisco on Monday. The new design direction was widely expected.

The software strives for a multi-layered look, with translucent panels. On the main screen, the background image moves with the movement of the phone, creating an illusion of depth.