You say someone has invented a smart phone that can do yet another thing that has nothing to do with making a call?
Check out this Samsung phone:
You can roll it up or fold it like a piece of paper. What a brilliant idea.
When the internet is down or the cell towers vaporized by the Russians and you’re trapped on the roof of a skyscraper simply fold the phone into a paper plane.
Write your message on the wing and toss it into the wind. Wait for rescue.