Storyline cards will appear peeking from the bottom of the Now Playing screen, allowing you to pull up on the card and read it while listening to the song. The card will disappear after some time, though you can stop it from going away by pressing and holding on the screen. Spotify Storylines may be made up of numerous cards containing text, lyrics highlights, and images. Tapping the right side of a card will move to the next part of the story, while tapping the left will go back.Similar to Instagram Stories, Spotify's implementation gives artists the complete freedom to share interesting facts about the process of making songs.
As noted by Android Police, Storylines are going live in the latest update for the Spotify app (version v188.8.131.523, to be exact). Seeing as how the feature is still in its infancy, not many artists seem to be using it. Give it a couple of weeks, though, and you're sure to see those cards start popping up in songs all over the place.