Musish - A web client for Apple Music
Playlist Machinery - Tools that help you create & organize your Spotify playlists
Festify - Festify is a free Spotify-powered app that lets your guests choose which music should be played...
Playlistor - Convert Apple Music playlists to Spotify and vice versa
Beatnik - Share music between streaming platforms
FreeYourMusic - Migrate from and to any music services