In both modes:
You have a certain amount of time to tap all of the red squares as fast as possible. Each red square is worth 1 point. Some squares are yellow instead of the normal red squares. These squares will give a certain amount of time of bonus. During this time, all squares will turn green and are worth 5 points. Also, the squares will spawn more often. If you tap and don't hit any squares, you lose 5 points.
In this mode you have 30 seconds and the bonus lasts 3 seconds. Also, yellow squares spawn more frequently in this mode.
In this mode you have 1 minute and 30 seconds and the bonus lasts 10 seconds. Also, yellow squares spawn less frequently in this mode.
Keep playing and compete for the highest score possible.