Is mobile messaging possible without data or wi-fi?
I found this startup's site www.bridgefy.me but is it possible? They may be on to something I kinda had an idea once to implement a data/wifi-less messaging system. They're probably going for P2P Wifi (ad-hoc) or bluetooth distributed messaging system. Basically the idea is...at some point people bump phones with each other...and given enough time...the message could be bumped to its intended desitination