While 2.2 introduced the legendary Platformer Mode (allowing left/right movement instead of auto-run), 2.21 polishes it.
Open the game. If you already have an older version, back up your save data (via Save in-game options). Geometry Dash 2.21 Apk
According to developer Robert Topala (RobTop), Update 2.21 is intended to be a "minor" update that includes features originally delayed from the massive 2.2 release: While 2