Yes. LoRa is a low bandwidth but high range radio. It allows you to cover a city. And its mesh, so it discovers the path through the city by itself. You can also use other links like wifi or an internet connection and it finds way automatically.

So you can have for example two houses connected with WiFi and each of them a LoRa node covering different parts of a city and you can send a packet from one side of the city, it is received by one radio, then to another house through WiFi and broadcasted over another radio to the other side of the city.

All of this is automatic and pretty dynamic.

There's an encrypted messenger that already works, I'm adding communication with the mint and we're ready for the apocalypse.