Which game engine? I don't think using Unity to make a UI app is great if you don't need the game-y features. It's UI functionally isn't the best since their UI

Which game engine? I don't think using Unity to make a UI app is great if you don't need the game-y features. It's UI functionally isn't the best since their UI Elements package is not quite ready for production use in games. Something like Dear Imgui can be very nice to work with though.