Would be cool with Arx Control for BeamNG. It's basicly an API that enables you to make interactive GUI on your Android device. That means everything from map view to speedometer. Pretty nice stuff, I imagine there could be a lot of cool things you could do with this. I don't think there's an open API for this (really not sure), so I can't make any claims on how easy it'd be to implement it into BeamNG.
No, not necessarily. But I don't see why they can make something similar with that API. Make it app-able and you'd basicly have the same thing, then we could se many different things in form of apps. Seems limited compared to Arx though. I'm thinking: having map view on there, as well as all the hud stuff, so that the game view is free from icons or text. And maybe car settings, world settings etc. That would be incredibly cool.
Based on what I've seen from other games using outgauge, I'm pretty sure apps like you are talking about are possible.