I'd like to better manage my mp3 player by having the capability to show comparisons between collections something like:
- found in mp3 player but not local collection
- found in local collection but not mp3 player
- found in both mp3 player and local collections

preferably (in my vision) there'd be 3 windows left mp3 player, right local collection and middle would be one of 3 comparisons described above. Tracks in middle window would be draggable to either left or right ones.

This would let me stop using foobar in a VM to sync my ipod (in other words, it's a good thing!)

Added it to kde bugzill as a wishlist item so please vote for it if you think you'd like the capability

https://bugs.kde.org/show_bug.cgi?id=205598