Plain physics is the main thing here. i think it is a simple grind.
Click to move and eat, you must grab golden apples to grow.
Controls are simple mouse clicks to move and eat. The main draw is collecting golden apples and avoiding poisoned ones.
Most helpful is to hold the mouse down to grab apples faster. You need to time your moves because physics are wonky.
Q: What are the controls? A: Click to move and eat.
Q: What is the objective? A: Grab golden apples to grow bigger.
Q: Is there a timer? A: Not stated.
Q: What is the main mechanic? A: Physics and eating apples.