Data. Image. The art of Keys Arrangement « Gems Sty. If you’ve ever wondered how they transitioned from rotary dialing to button-press on the telephone, here’s an interesting background story. Before it became a standard that every phone now follows, human factor specialists (or the equivalent in those time) actually tested 18 different possible key layouts: The participants were asked to key in a bunch of numbers and timed for it. Other factors like aesthetics and error rates were also computed. The five finalists were as follows: The Future of the Book.