@slarti76
Locus & Pokémon GO 
Guilty pleasure...

Thanks for the tests! You were really able to resize and move this PiP window fully freely? Weird, it should not be possible.
Well, as I said, ratio was fixed, but I could make it much bigger. Is that really not supposed to be possible? I mean, e.g. if I use VLC as pop-up, I can resize it to like 90% of the screen width (but also the ratio is fixed).
Ah, I just realized something: A video is, of course, in landscape - so resizing to full width is possible. Locus was initially 1:1, which obviously also allowed it. Once you changed the ratio to 3:2, it's not possible anymore, because then you could basically resize it the more or less full screen size. So Android doesn't allow it. Of course it's ridiculous why Android forces this on the user, also that snapping to left or right of screen, but we all know Google...
Does that sound like a possible explanation to you? (I don't have a portrait video around that I could try with VLC...)
Anyway, perhaps you could at least let the user choose whether it wants the pop-up in portrait, landscape, or square. Everything after that is Android, and we have to live with it. But 3:2 portrait is very likely not what you want in every situation...
It is also not possible to define own custom buttons there. For this, you may simply use the split-screen mode of your device, you do not need a PiP.
Sure, ok. But then why have that bar at all? As I said, just put the Navi Icon in the upper left and voilà - space saved...
Anyway
- map rotation > agree, I'll look at it.
Thx
- map zoom > there should be no changes when switching to PiP, so you should see a zoom visible on current map.
Oh, you're right, didn't realize that. However, I had "Automatic Zooming" on, and that doesn't seem to work in PIP - could that be enabled there, too?