What happened: Text messaging seemed to be the go to service, after that the solution was to find a tower that had signal and then go there. People were parking as soon as their phones started registering service, massive comms traffic jams formed. So even in place with service the cell would become swamped, again text messaging's small footprint allowed messages to squeeze out. If you stay connected long enough there was a dribble of IP. However, any platform that required "server" processing was disrupted. I heard that SnapChat was useful to send messages because the packets were small enough to squeeze through, but connecting to the servers for validation to login was troubled. One other observation, smartphone apps that have fully functional Internet websites seemed to fair better, think Facebook, Netflix, Torrent; Apps that can function on very low bandwidth are the key.
Contemplating: I need to challenge the "build it and they will come" approach here, so I'd rather approach it from the simplest system possible. Is that peer-to-peer text messaging? That's my current hypothesis until I can learn more.