I'm working on building a generic desktop controller that you can run from any device. https://github.com/jonocodes/deckd

Originally inspired by the stream deck, but I wanted a more dynamic interface and less hardware restrictions. For example you can use your phone as the controller.

Now it can do a whole lot more. Including mouse, keyboard, media controls. Supports custom buttons types and things like sliders and color pickers. Dynamically switches layout based on foreground app, and can also control which app is in the foreground from the controller itself. Having a lot of fun so there are a bunch more features in the hopper like deeper app integration, and an eink version.

Its a web app/PWA, so no app store needed.