SoundHound has teamed up with Spotify to make it easy for you to create a playlist of songs you've identified. Now with "Hey SoundHound", adding to that playlist has never been easier. After identifying a song, simply say, "OK Hound, add this to my Spotify playlist."
You can actually add songs whenever you feel the urge; you don't have to wait until you identify one. For example, you can say something like "Hey SoundHound, add "Nobody Love" by Tori Kelly to my Spotify playlist."
SoundHound Support Center