⛽ Happy Gas Station
Hold the button to let fuel flow into a big see-through tank, then let go right when the number of litres is reached. Extra pours into a spare can.
Press and hold the round ⛽ button in the corner to pump: fuel flows into the tank, the big number on the pump climbs and the needle turns; let go and it stops, so you can hold and release as many times as you like to inch closer. After you let go, a small ring runs around the number for about a second and then the amount is locked in; holding again cancels it. In Learn-to-count the fuel rises one liter per click so counting along is enough; in Steady-hand it flows continuously and you should release when the number is within about half a liter of the target. Overfill and the extra fuel just pours into the spare can, then a new car pulls in with a new number.