PeerTube apps are quite disappointing at the moment, in my opinion.
Peertube
A free software to take back control of your videos
Peertube is an open, federated alternative to Youtube without advertising or tracking. On this site, you can find a good Peertube instance, with good rules, good moderation and most importantly a friendly community.
I don't know... I use FediLab every day to check out new videos on the bus to work (it's a very short bus ride :)) and like it. Maybe I'm easily pleased.
In your opinion, how good is the viewing experience of Peertube videos on FediLab?
It seems fine. The player's interface is very comparable to NewPipe's. It goes fullscreen when you rotate the phone in landscape mode. It starts quickly, it doesn't stutter. No complaints.
I haven't used it very much yet though. Maybe I'll be hit by a really annoying bug I haven't bumped into yet. But so far so good.
EDIT: mind you, I just wanted to be able to comment on videos logged in. If the player turns out to be crap, I can always fall back on NewPipe: it plays PeerTube too, just not logged in.