Medley is a music player that looks like the pre-iOS 6 Music app.
Medley is not a pixel-perfect re-creation of the Music app. For example, it uses San Francisco instead of Helvetica, and almost all the icons are SF Symbols. You can play music from Apple Music if you’ve already added them to your music library. But Medley doesn’t support browsing the Apple Music catalog or adding songs from Apple Music into your library.