Trill

Trill makes your Mac's trackpad do more, and taps back when it does.

Record a gesture by simply doing it, or start from ready-made gesture sets. Caps Lock becomes a Hyper Key that adds Control, Option, Shift and Command; a tap alone sends Escape, and holding it shows a cheat sheet of shortcuts for the app in front. Drag-to-snap window management is built in, and on Force Touch trackpads every gesture gets a haptic tick.

$29 once, with a 24-hour free trial that starts when you allow Accessibility. One license covers three Macs.