YouTube is a giant platform — over 300 hours of video are uploaded every minute. It can be difficult to keep track of your favorite videos in such a chaotic sea of content. Difficult, but certainly not impossible.
Downloading YouTube videos for offline use to watch later has always been a problematic endeavor. Dedicated third-party apps don't last long in the App Store, web-based converters aren't very functional on mobile, and rogue apps outside the App Store are tricky to sideload and open up the possibility of vulnerabilities. But that doesn't mean you still don't have a few good options.