[nvrg]

Very esoteric app, however I think Ymusic needs to be mentioned whenever YT alternatives are brought up. It streams only the MP3 of the video and the UI is cleaner imo - so it's easier to use if you intend to only listen to "podcasts" or music as an alternative to Spotify.

[no-reply]

Don't know about Ymusic as it doesn't seem open source, but seal [0] seems like a good alternative, based on yt-dlp

0: https://github.com/JunkFood02/Seal

[KAKAN]

There's also ViMusic, which is open source: https://github.com/vfsfitvnm/ViMusic/

[crtasm]

Sounds good. Newpipe can stream audio only too.