Commands

Arrows / WASD / pad: turn. One press is one turn (holding doesn't repeat). Up to three quick turns are buffered, so fast zig-zags work.
Swipe anywhere on the arena to turn that way, or tap beside the head: above or below it when you're moving sideways, left or right when you're moving up or down.
Enter / Space / OK: start a stage (so does any arrow or swipe).
Backspace / B: press twice during a stage to give up. On the map or the skins list it goes back to the menu.
Star map: arrows pick a stage (Up/Down jumps a world). OK or a second tap plays it.
Menu: 1 Campaign, 2 Classic, 3 Endless (Daily Orbit in Daily mode), 4 Skins, 5 Log off (press twice).
P / Esc: pause.
Choices menu: pause, how to play, new game, sound, difficulty, save slot, theme.