Gravity Balls is a relaxing physics sandbox where a set of colourful balls fall, bounce and jostle against each other and the walls — and gravity points wherever you tilt.
How it works. A proper physics engine runs behind the scenes. Each frame is broken into several small sub-steps, and within each step the app nudges every ball's velocity by gravity, then repeatedly resolves collisions — ball-against-wall and ball-against-ball — using impulses that account for each ball's mass (bigger balls are heavier), bounciness and friction. This iterative approach lets balls pile up and settle into stable stacks instead of jittering or sinking through one another. Drawing is just as efficient: a single instanced WebGL2 draw call renders every ball from one shared shape, and a shader turns each into a crisp, smoothly anti-aliased disc.
How you interact:
- Tilt to steer gravity — on a device with a motion sensor, physically tilting it pulls the balls in that direction (the display reads IMU LIVE).
- Drag — with no motion sensor, dragging on the screen points gravity toward your finger instead.
- Full screen — fills the display for the full effect.
A lightweight, self-contained demo that runs completely offline.