Skip Tunes - Control iTunes, Spotify, or Rdio from your Mac's menubar
Soundiiz - Transferring playlists between various music streaming platforms.
SpotiMy - Play/Pause and Next/Previous functions for Spotify directly on your Menu Bar!
Musconv - MusConv Tool is powerful music migration program.
Bowtie - Bowtie is a desktop accessory that allows you to see and control your music (iTunes, Spotify...
Tune My Music - Transfer Playlists Between Music Services