Controlly lets you use the controller that came with your Sony or Microsoft gaming console as a remote control for your Mac.
This can be especially helpful when, for example, streaming your favorite TV show from a Mac to your telly in the living room via AirPlay but couldn't be bothered to get up and sit in front of the computer just to select another show.
Controlly is a new app by developer Hugo Lispector that makes it very easy to navigate the entirety of the macOS user interface with your PlayStation and Xbox controllers.