So I’ve heard about some Of the people in an African nation (sorry don’t know what one) they are using sms to transfer bitcoin and honestly I feel like this should be fleshed out to be really reliable and foolproof.

Yes it doesn’t solve a dead battery but it does solve localised internet dropouts.

If the wider internet does drop out does being able to broadcast via your own relay network, wonder if you could cover enough distance to do p2p transactions over a local network