This means users can control the app through supported systems. Spotify was listed as one of very few app launch partners for CarPlay, and was included in a demo we checked out back in March.
Similar services like Beats Music, iHeartRadio and Stitcher have also pledged to support the system. Virtually every major manufacturer has promised to include CarPlay in their vehicles at some point, although at the moment your only options are to buy a Ferrari FF or an aftermarket unit from Pioneer.