Federico Viticci 
I wrote about how I'm using the Play app as a secondary YouTube client for watch later across my iPhone, iPad, and Vision Pro: https://club.macstories.net/posts/switching-to-play-as-my-secondary-youtube-client
Anthony@viticci I haven’t noticed issues with Unwatched sync mainly because I use it as a triage system on my iPhone. Unwatched has all my subscriptions. Once a day (usually in the morning), I go into Unwatched and pick what I want. Some stuff that won’t play in third party apps *cough* The Official Pokémon Channel *cough* goes to my Unwatched queue since it works there. The rest gets shared to Play. It’s liberating not having the YouTube app on my phone anymore.
Aaron David Kovalchik@viticci does it keep playing audio when the screen is locked?