Designer Frank Costa uses his iPhone 6 Plus for lots of things, but he noticed that when typing on it one-handed, the anatomy of his thumb use wasn’t as ergonomic as it could be.
Costa decided to design a new kind of keyboard for the thumbs, one that would only need you to tap and then move your thumb a short distance away from wherever you tapped. This would require less stretch and — perhaps — less stress on the thumb joints.
“So, being a designer,” Costa writes on Medium, “I played with the idea of a keyboard thought (out) for the thumb. A keyboard requiring only a single tap and some short swiping to construct words and sentences.”