I don't know if it is already possible, but I find that it is very confusing when you have a music sheet PDF and iRealb at the same time, you have to change from one to the other very fast and one overlaps the other. I think it would be very useful if you can put iRealb in a "miniplayer" state, like iTunes does. Then, you can have the notes PDF and the miniplayer at a side and hit play, stop, pause, etc. at any time without hiding the PDF.
It would be useful also if you could skip to the next song in the playlist from there also.

thank you for your wonderful program

cronban