Ellis Hamburger with a nice discussion about designing for iOS 7.
To Ive, iOS 7 is about more than a dash of color and Helvetica Neue. It’s about the physicality of the operating system, a functional skeuomorphism which helps people identify layers within apps as if they were papers on a desk. "It’s no longer about mimicking real-life objects visually, it’s about how they work, and the way things move and interact with your finger, and the rest of the elements on the screen," says Jeff Broderick, who co-founded software design studio Collective Ray, and is now creative director at ShopSavvy.
I think a good way of describing this aspect of the iOS 7 design ethos is “spatial stability” or “spatial consistency.” The on-screen environment is context rich and that context is preserved wherever possible through natural, in-place transitions rather than disrupted through more abstract transitions. Objects on screen move as they would in the real world, creating interactions that feel much more natural and familiar.
This is far more important than having static objects on the screen look natural or familiar. It creates an experience that reduces the cognitive load on the user while also introducing an element of playfulness that can even lead to delight.