There is also TouchControl. It’s iPad/iPhone/PC only. It’s definitely DIY, but the limit is your imagination. You have full control of the screen. You can use traditional command buttons, one per command, or a “button” could be a web page that you’ve built. If a device, such as ROKU or MusicCast offers a reasonable (documented) API, you can integrate that with your program. Or, you can simply call the native App.