Try cobalt.tools. It does what you want to do inside a browser tab (although I only used it on desktop so far), but it might work with an IPhone as well. You can convert YouTube links into either mp3, ogg, wave and opus files (with various bitrates), or mp4 or webm video files (with various resulutions). I use it constantly.

The “invite your boss for dinner to your home” thing that is often depicted in (US-based) sitcoms or cartoon series, where the protagonist introduces the family to the boss who is invited to have dinner at their home in anticipation to get a raise and/ or promotion. Is that a real thing over there? I never would think of invitng my boss into my home.

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