digito. gives you a target and a single digit. Reach the target using only that digit and math operators — 33 + 3! ÷ 3 = 35. Anyone can solve it; the game is doing it in the fewest digits, and the expression evaluates live as you type, so there's no submit button and no timer. Daily and weekly challenges, nine number worlds of 999 levels, many achievement badges to stumble into, two hand-built themes. Free to play. iOS, Android and online web demo (world 4 + daily).
