Tilt the tray by swiping on it or tapping the arrow buttons. Every marble rolls until it hits a wall or another marble. A marble falls into the hole of its own colour and rolls over the other holes. Get every marble into its hole. Par is the fewest tilts that can do it. Finish the first tray to unlock the second one, with three marbles.
On a phone, ⋯ → Tilt to play lets you tilt the phone itself: hold it as you like, switch it on, then tip it — the tray leans with your hand and the marbles roll when it leans far enough. Level it again before the next tilt; double-tap the tray to make where you hold it level again. Every tilt counts, so a twitch counts too — Undo takes it back.
Keys: arrows tilt, Z undoes.