Play/Pause should always be directed to the last media app that had control about media-button-router HOT 4 OPEN

I think, mbr should always ask after pause. So it is possible to change the 
player
without grabbing the phone.
I have this behaviour:
I often listen to podcasts in my car via BT with BeyondPod or AntennaPod.
On work I use Poweramp or Apollo to play music.
Back in my car, and hitting play, the last used (music) player starts directly.
I have to grab the phone and change to a podcast player.

Then you always have an interruption whenever you hit play! That's worse! How 
do you change players without grabbing the phone?

For example I hit play and choose apollo, apollo plays. I hit pause,
apollo stops. I hit play again, mbr should ask me again, what player
to use. So I could switch to antennapod or something without grabbing
the phone. By now, apollo starts playing again. mbr does not ask me
again.

Oh I understand what you're asking for. Just seems to me when I think about it 
that more often than not when I hit play I want to play what I was playing 
before, not switch to another app. So, for example, I might be listening to a 
podcast in the car. I might get out to go to a store, waiting in line I'll 
listen to the podcast some more. Get back in the car and I would want to resume 
my podcast. Maybe later I would want to switch to music. Still, in this 
scenario I wanted to play the same stream 3 times vs. 1 time to switch. IMHO 
whatever happens the most frequent should be the default action.

BTW I no longer use this app as I've moved to a Galaxy Note 3 and the Bluetooth 
stuff performs much better, usually restarting what I was last playing. The 
previous phones I had had had (shit 3 hads! That's never happened before!) 
problems with Bluetooth and this app helped. YMMV