TubeLister - Generate a YouTube playlist from your opened tabs.
Tuned Rocks📺 - Discover🔎 curated Youtube videos 24/7
Vidlis - Create music playlists from YouTube videos.
Playmoss - Create playlists from YouTube, Vimeo and SoundCloud
NewPipe - NewPipe is a lightweight YouTube front-end for Android.
Quite a Playlist - Find deleted & private video details from YouTube playlists