Sideband app
Sideband is Messaging tool that is open source under the CC-BY-NC-SA license.Sideband is a LXMF client for Android, Linux and macOS allowing you to communicate with people or LXMF-compatible systems over Reticulum networks using LoRa, Packet Radio, WiFi, I2P, or anything else Reticulum supports.
Sideband is completely free, permission-less, anonymous and infrastructure-less. Sideband uses the peer-to-peer and distributed messaging system LXMF. There is no sign-up, no service providers, no "end-user license agreements", no data theft and no surveillance. You own the system.
This also means that Sideband operates differently than what you might be used to. It does not need a connection to a server on the Internet to function, and you do not have an account anywhere. Please read the Guide section included in the program, to get an understanding of how Sideband differs from other messaging systems.