Downloading YouTube videos on Android for offline viewing later

One of the all-time great tools of the internet era is youtube-dl. It enables you to download any YouTube video for watching offline/later. It has been a fantastic boon over the years for watching all my hundreds of subscribed channels when in planes, trains, automobiles and treadmills. It’s also the basis for my own YTPodders tool for generating podcasts from videos. Normally I run it on the PC and copy the files to the mobile devices, tablets or media players. »