105
Google could kill YouTube Vanced for good
(www.androidpolice.com)
This is a most excellent place for technology news and articles.
To play video, the YouTube app does API calls directly to the YouTube API instead of loading any web code, then gets a reference to the media to play back and plays it back in a native media playback SDK.
Revanced does their stuff the way they do by manipulating the bytecode that the YouTube app consists of, to add/remove things.