Consists in:
A circle will appear on the screen, game area, periodically, a predetermined number of times, randomly varying the place of appearance in the game area, the player must catch them by touching the circle, it will have a predetermined time to do it and must do it in a single attempt, at the end, after all the determined appearances, the number of circles caught will be displayed on the number of appearances.
You can define the background color of the playing area, the color of the circle, the periodic speed of the appearance of the circle, the size of the circle and the number of times of appearance of the circle.