The Messages app on iOS has a feature that seems intended to prevent spam messages from appearing in the list of messages I see by default: choosing to filter on "Known" senders only. I'd have thought that this would filter out spam messages from unknown numbers, but that's not what it does, so I constantly get such messages appearing as "Known":
What does "Known" actually mean? How do I use it or some other feature to prevent spam from unknown addresses from appearing in Messages?
