MusicPiped
A music player that streams youtube
Music Piped is a free and open source full-featured Music Player that instead of playing local Music files streams from internet.

Forget dowloading music from internet, forget streaming music from video streaming services.

It's all in one place now, just search and and play almost all music free.
The app is completely free open source, features no IAP, non intrusive ads. Just download app, search your song, and stream!

Features an inbuilt search to search, an adjustable playing queue, custom playlists and more. No song is stored in device it's directly streamed from google server hence saving space.

It does not streams video and only fetches audio files thus eliminating heavy data usage of videos,
It's full featured music player so you can enjoy background playback with notification controls, customisable queue, repeat and shuffle.
It does not track you, there is no tracking system at all, you don't even need Google APIs to use app.

*While streaming keep in mind that you only stream music in public domain.

License
App is licensed under GNU GPL v3

Source
https://github.com/deep-gaurav/MusicPiped

Following libraries are used with license
NewPipeExtractor - GPL v3
Picasso - Apache 2.0
ExoMedia - Apache 2.0
Android Video Cache - Apache 2.0