aa is General Adaptive's flagship "focused, minimalist" puzzle game, and while focused and minimalist sounds more like a way to describe architecture than a game, aa makes for one seriously addicting app. The 600 levels are insanely addicting and insanely tough, but every level has its own strategy that enables a fairly easy victory.
aa is a new "minimalist, focused" app in a series of two-letter games for the iOS and Android platform by General Adaptive Apps Pty Ltd (short game name, long developer name). They call it the game to end all games and a great anti-game. Your humble author calls it an insanely difficult, frustrating and addicting quest through more than 600 levels of figuring out how to attach the little ball to the big ball.