Control the paddle by keeping your finger pressed. Break all bricks to finish the level. Chose an upgrade and play the next level. Try to catch all coins, never miss a brick, and clear levels quickly to upgrade better and faster. Many upgrades increase the "combo", a number shown on your paddle, which determines how many coins are dropped when you break a brick.
This game is open source, ad free, does not track you, and works offline. It is under 1MB and should run smoothly on old android devices. There's also a web version you can use without installing anything.