The ESP-32-based M5Stick-C is a wee, super portable, open-source IoT development board, like a fun-sized version of the M5Stack. https://elecena.pl/product/17502382/m5stick-c-pico-mini-iot-development-board 2021-04-07 https://elecena.pl/product/17502382/m5stick-c-pico-mini-iot-development-board 2022-01-15