“This is a fairly simple add-on for mobile phones to enable SMS-like messaging in a group when outside cell coverage, or in disaster scenarios. It utilises Semtech LoRa radios, for low-power/long-range communications. There are a lot of hardware options, and I am still trying different devices and manufacturers, but for now this tutorial will show how to assemble and setup one of the following boards:
TTGO ESP32 Lora with OLED
Adafruit Feather M0 RFM96
Supplies:
The hardware can be purchased here:
TTGO ESP32 Lora with OLED . -OR-
Adafruit Feather M0 RFM95
Optional items, but recommended are:
small on/off switch
Piezo buzzer
small 1S Lipo battery
USB OTG cable”