Why it worksThe bars are a little chart. A steady rise is bars growing one by one, and a sharp fall is the tallest bar followed straight away by the shortest.

Why it worksEach tap turns a line a quarter of a turn. When a line points at a square or triangle, it lights up, so you keep turning until every shape has exactly the right number of connections.

Why it worksThe heading itself contains the letters you need. Tapping them in order spells BOO and scares the ball.

Why it worksEvery dash is a minus sign until you turn it into a plus. Each corner has the pair of signs shown, and dragging a plus from the centre makes the change.

Why it worksThe colours change one tap at a time and each button has its own number of taps. The ones in the middle need somewhere in between, so tap until they change.

Why it worksEach word in the list crosses off when you make that shape. The four handles are enough for all of them, as long as you move the corners the right way.

Why it worksThe level wants you to copy the column. The white box is your carrier, and the balls have to be picked up in the same order as the ones above.

Why it worksThe clock isn’t broken, it’s just wrong. The level compares it with your phone’s time, so the right answer is different for everyone.

Why it worksThe triangle only changes direction at blocks, so the blocks decide its route. Placing them in those five spots makes it visit the balls in the right order.

Why it worksThe ball follows gravity, so tilting steers it. The route goes all the way round the outside of the middle box to reach the exit at the top left. Try not to touch the walls on the way.