No information is collected by Notify for Spotify.
Notify for Spotify displays local notifications for the purpose of displaying actively playing songs in Spotify. It requests permissions to control Spotify for the purpose of retrieving the active playing song, going to the previous song, and going to the next song.
It makes an outbound network connection to retrieve artwork from Spotify.
Notify for Spotify is a third-party app, unaffliated with the company Spotify AB.