Enjoy!
You begin on the right hand side of your screen, heading left, while descending as the name of the game implies. To switch direction, tap the screen. Rather than making a curved turn like in Rally Legend, the arrow turns abruptly in a zig zag pattern. Each stage spans 500 points. The first and last 75 points (0-75, 425-500, 500-575, etc) are free of any obstacles. In between, you are met with two obstacles, pillars and squares. Touching them will cause an immediate game over.