iOS... I had the gloss look 3 years before the iPhone was released, then when I got tired of that style, I went for the flat look. iOS 7 (I think) did the same a year later.
My latest design is actually a combination of flat buttons with virtual remotes. It works very well, at least from the feedback I get from dealers.
[Link: blackmancustoms.com]I am porting this to Crestron Construct as we speak.