PocketTube - Group YouTube subscriptions into YouTube folder. Video Deck for Youtube. Mark as watched videos. Filter YouTube video. Youtube mode
Video Deck for YouTube - Control videos that are uploaded by your favourite YouTube channels.
PlamasTube - Video & Movies
YouTube Vanced - Vanced is a modded version of YouTube with many features such as adblocking and background playback
NewPipe - NewPipe is a lightweight YouTube front-end for Android.
Invidious.io - Invidious is an alternative front-end to YouTube.