The application is a minimalist puzzle, to pass levels which is simply impossible without knowledge of the physics of the movement of objects. Therefore, it is necessary to recall everything that once had to be taught in school during physics lessons.
At any level, you will have to move a small red ball, which should fall into a strange green container, which looks quite like a magnet, but is green.
But if everything was so simple, the game simply would not be interesting. Your ball will face a wide variety of obstacles in the form of blocks, walls, and so on. If you do not want to replay the level again, have the ball get a stable line, reinforced with supports.
Secrets of the game
At certain levels, you can do without drawing lines. Just force the ball in the right direction. You just need to draw a line behind the ball, and this should be done with a sharp movement.