I just took a quick glance but it appears to be a fork of newpipe rather than a fully separate project.
It adds a couple sources that I am unfamiliar with (BiliBili? NicoNico?)
Also the developer says this about it:
This project is for my personal use. If you open an issue I won’t encounter, most likely I will not make any fixes.
Personally I don’t see a reason to use this (or the other half dozen alternatives on Android over Newpipe which works great for my needs, and seems to be the most mature and reputable youtube frontend for Android. But if PipePipe appeals to you, give it a try let us know how it is.
I am super happy with the combination of Newpipe for Android + Freetube for Desktop. Unfortunatley I’m on the iOS side of the fence now and there is nothing comparable yet, I have hope for Yattee but it has a ways to go.