Heavy things bend space around them, like a bowling ball on a stretchy sheet.
Marbles you flick aren't pushed by a force — they just roll straight, but the bent sheet curves their path.
In Flick mode, drag back and let go — the arrow shows your aim and speed. In +Mass mode, tap to add more heavy stars. Try the Binary button for two stars dancing together!
That curve is gravity! Some marbles fall in, some swing into orbits, just like planets around the Sun.