MusicPiped is a full-featured music player that streams from YouTube instead of playing local files.
You can stream any music available on YouTube for free.
At core this app uses NewPipeExtractor to get streams from YouTube hence can play almost any YouTube stream.
Features an inbuilt search over YouTube, an adjustable playing queue, custom playlists and more. No song is stored on your device, they're directly streamed from Google servers, hence saving disk space.
It does not stream video and only fetches audio files, thus eliminating heavy data usage of videos.
It's a fully featured music player so you can enjoy background playback with notification controls, and you don't need to keep screen on and focused to listen to your music.
It does not track you, there is no tracking system at all, you don't even need Google APIs to use the app.