[SmashTunes 在Mac App Store上售价18元]
SmashTunes is a very nice menu bar item that lets you control iTunes as well as Spotify. It displays information about the currently playing song as well and can also display artwork.
SmashTunes also makes your media keys work with iTunes and Spotify better. When you use them for iTunes they will control iTunes. When you use them for Spotify they will control Spotify. Either app will be paused when the other starts playing. No more sound mixing. No more manual stop action of either app is required!