I present to you The Knob of Contrast (sounds epic, eh?) which serves the purpose of.... adjusting contrast? This is the latest artwork I did for Samplephonics, called
Skeuomorphism in User Interface Design, What is It? - Designmodo
power button design - Google Search
Free Icons for Web and User Interface Design
This app is a nice change from the standard iOS7 apps that have been getting released lately. Its still has a nice clean design but it also involves more complicated elements that make for a nice relaxing interface.
UI design - Micro interface
UI wheel and buttons properly termed constraint buttons. Wherever an intrinsic scale is present you can be sure constraint buttons are in the mix. Further more the circle or wheel design offers economy of design