Squishy Slime Maker

Squishy Slime Maker is listed here under Hypercasual. There is no launcher and no install between you and it. Designed around touch input, and comfortable on a small screen. Tagged coloring, magic, simulator.

It is drawn for a tall screen, so it fills a phone held upright rather than a wide monitor. It costs nothing and asks for nothing: no registration, no download, no launcher.