FreeTube - FreeTube is an open source desktop YouTube player built with privacy in mind.
4K Download Online - Download music from YouTube to Android, SoundCloud to Android, Facebook to Android, Vimeo to Android, from browser to device or to desktop directly.
NewPipe - NewPipe is a lightweight YouTube front-end for Android.
ImTOO Download YouTube Video - ImTOO Download YouTube Video is a free YouTube video downloader software!
Minitube - Minitube is a YouTube desktop application.
Video Downloader Professional - Video Downloader Professional (VDP) is an pretty smart and fast tool to catch videos from YouTube.