[meibo]

It explicitly doesn't provide Premium for free, all premium features but the picture in picture support are still locked behind purchase.

The standout features are ad- and sponsorblock.

[xwx]

Huh, interesting. Maybe it's changed, maybe I'm misremembering.

In either case NewPipe has picture-in-picture playback and audio only playback. Not sure what else I'm missing from Premium.