I run Roon Remote on a couple Minix Neo U1’s - they run Android 5.1.1 (apps see as a tablet) streaming to some ODroid C1+'s.
The interface looks fantastic on the TV but doesn’t respond to the arrow buttons on the remote - works fine though when I use the air mouse functionality of the remote (this is my current workaround).
Any chance to update the app to respond to arrow key inputs?
The browsers do response to arrows. Open the app on your Mac/PC and hit arrows to see.
However, what you want is a full UI focus model that supports the current thing you can click on. The Roon UI is far too complex for use like that. We have some ideas on how to pull off a TV based UI, but that work has not started yet.