Move your mouse / drag your finger left-right (or use arrow keys) to tilt the platform and roll the ball. Don't let it fall off the ends or drop through a hole. The platform shrinks and holes appear as you survive longer.
Tilt Balance hands you a platform that keeps shrinking from both ends while random holes open up in the middle, and you're just trying to keep a ball rolling on what's left. Free to play, and the longer you survive, the less platform you get to work with.