It's still not getting completely away from Google, and they could probably still track you through IP, but I've been really happy with the NewPipe client for Android; it's attempting to provide all the features of browsing without falling back on any official API and certainly without needing an account. There are a few features that aren't out yet (most notably comments, notifications, and YT-user playlists, though it can play the latter if you get the link through another browser) but it gives you an offline subscription list and in my opinion is more comfortable to use than the official app.