Google quickly strikes them down, so they never lasted long. Over the years, countless apps and methods have surfaced for bypassing YouTube's restrictions and downloading YouTube videos to your iPhone's media library.
With the Workflow-replacement app, you can add a shortcut that lets you download any YouTube video you want, without needing to jailbreak or use shady third-party tools.
If you've ever wanted to download YouTube videos directly to your iPhone, there's an easy solution - just update to iOS 12 and install Apple's new Shortcuts app.