A platform to enable affordable sensor networks
The best source of information is the Wiki here
Frugal-IoT is a library, available on both PlatformIO and Arduino repositories.
It is intended to run with a backend server in the frugal-iot-server repo; and with frugal-iot-client which works on mobile or laptop. There is also a server-side logging tool, that drives the graphs in the client, or can output (live) to Firebase and Google Sheets.
It enables really simple applications to include a full range of functionality, such as wireless & MQTT reconnections; LoRa meshing; access to functions like time; various sleep modes.
It works on an expanding variety of dev boards; with an expanding range of sensors, and in an expanding range of languages.
But ... please see the Wiki here, which - unlike this README is updated regularly.