You tap the screen (or press) to cause the planet (or the surface) to twist or rotate. This changes where obstacles appear relative to your hero.
As the planet twists, obstacles rotate into your path. You must time your taps so that you don’t collide with these obstacles. If you hit one, the game likely ends (you lose).
Alongside avoiding dangers, you can collect “foods” (or collectible items) as you go. These add to your score.
The main objective is to survive as long as possible while collecting items to increase your score. The longer you live and the more items you gather, the higher your score.
While not explicitly detailed in the App Store text, most games of this style gradually increase the speed, frequency, or complexity of obstacle placement as you play longer, making it harder to avoid collisions.