Japanese hiragana keyboard for Android. It' shaped like a circle and you write by swiping towards choices. It's fast but it's not a complete Japanese keyboard. More of a proof of concept. Also a good example code if you want to make your own unconventional keyboard for Android.
Quiz game.
It virtually draws "cards": first you can see the question and guess the answer. Then you can see the "answer" side of the card. Program registers if it matches or not.