Looking Beyond The (Flat) Surface
There’s been a lot of knee-jerk reactions to iOS 7's overhauled user interface but it’s disappointing that most of the criticism are sweeping generalizations of the entire UI based on a few aspects of the surface aesthetics. It’s easy to make fun of the “ugly” icons and the neon colors and leave it at that but it’s more interesting to go deeper and understand the design choices fitted to a flat UI.
Design is about working with constraints
It’s easy when you have the full arsenal of design elements to communicate with, to tell the user which part of the content contains the information they need, what can be interacted with, and how to use an interface element, etc. It’s just as easy to produce a cluttered design that lacks subtlety. iOS 6's skeuomorphic design takes the visual metaphor too far at times. It feels like you’re being shouted at from every angle, each time you use it, everyday. The novelty of lush high-def visuals wears off quickly.
Flat design subdues design elements that mimic reality––gradients, drop shadows, textures, etc. To compensate for the loss of delineation and clarity of function, the designer has to effectively use typography, color and scale. You got to reduce overall contrast so that the elements that matter (such as buttons) can be distinguished.
Compensating for affordance
The lack of affordance in flat interface design is why it only makes sense to use it when the user is already familiar with the rules and interaction patterns of a UI. This is the case with iOS 7 and it is also why everything looks different but very little underlying has changed. The buttons are still where they were, wrapped around the title in the navigation bar. The gestures to navigate views, to pull down notifications, to unlock the screen are the same. The new gestures to go back a screen and to pull up the new control center are built on the existing interaction paradigms.
Why flat design then? It is lighter and lightness gives the illusion of speed. Lightness is also important for daily repeated use. It showcases the content instead of vying for attention in the limited space of a mobile screen. It places function over aesthetics.
Flat design can be misunderstood as a visual style and abused to create indulgent design. I feel that way towards Windows 8. iOS 7 is flat design done right. What is interesting to me is how Apples goes a step further in creating delineation with perceived depth (background blurring) and motion (transitional animations). Edward Tufte’s information design principles are more important than ever as we transition to an age of functional design.