The public beta tests of the new Briar messaging system have been set up to ensure maximum confidentiality without the use of any centralized servers.
Briar works in P2P mode where users connect directly to each other. It is possible to use the anonymous Tor network, but Briar can operate without any internet connection - sharing data via Wi-Fi or Bluetooth.
The client program is a mobile Android messenger app. Provides messaging, access to public and any other forums, closed chat, statuses, RSS feeds.
The main goal of Briar developers is to create a decentralized system that enables people to create free spaces for communication, event planning, and organizing free initiatives, all of which can’t be restricted by censorship, can’t overhear and can’t Be blocked.
The source code and cryptographic methods used have already passed the safety audit of Cure53.
It is planned to create a desktop PC version, the ultimate goal being to create a unified P2P system for collaborative document handling and critical situation analysis.
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Is this like mesh-networking?
Yes, but in addition to Wi-Fi the system can use Bluetooth (which was the most surprising thing for me) as well.
That's interesting, but if you think about it, all cellphones are dead in the water when cell towers die. They could as well communicate and route traffic between each other but that is not what the powers wanted.