Marble Run

Tap a course to start it. They are all there from the start, and you can play them in any order. The ◀ ALL COURSES tab in the top corner takes you back to the list at any time, and after a race there are AGAIN and NEXT ▶ buttons.

Rub the pad the way you want to roll, like spinning a ball in its socket. Rub harder to push harder, and lift your thumb to rub again. Resting your thumb on it does nothing. On a computer, use the arrow keys: up is up the screen, and two keys at once roll straight along a path. 1 2 3 4 pick a course, and Esc goes back to the list.

Downhill speeds you up and uphill slows you down. Pushing only gets you so fast — a slope takes you faster than that.

A red edge is a drop that breaks your marble. A coloured edge is a small step, and you are fine. In the air, watch your shadow: that is where you will land.

A broken marble costs time, not a life. A new one appears at the last safe spot, and the clock keeps running.

Stompers glow red, then drop. Roll underneath while they are up. Lifts go up and down — wait until one is level with you. Fans blow you sideways. Ice: you can hardly push and hardly stop. Goo slows you right down, which is sometimes handy. And the bully marble is heavier than you, and grumpy. It can fall off too.

Round and Round is a ring, and you go round it twice. Rolling over a checkpoint ring lights it up gold; once all three are lit, crossing the finish line counts a lap. So you cannot cut the corner — you have to go all the way round.

Every course has its own best times.