The ESP32 devices offer better features than the famous Arduino (native Wi-Fi/Bluetooth dual communication, size, processor, memory, price) while using (among others) the same programming environment (Arduno IDE), putting together better performance and easy programming.
The ESP32 becomes a really interesting option for developing Litems:
- using BLE both overcomes the Classic Bluetooth piconet size (max. 7 bluetooth slaves connected) and allows developing the concentrator as a software layer on a BLE enabled device (Raspberry Pi 3, any modern tablet or laptop),
- it offers enough processor power for developing virtually anything,
- its cost and size are reduced,
- being based on Arduino IDE, the programming learning curve is really short (there are thousands of examples and tutorials in Internet).
For a "Getting started" guide, visit Random Nerd Tutorials site.
For full information, visit the ESP 32 site.
Update (01/21)
An interesting option regarding small footprint is the SiP (System in Package) ESP32-PICO-D4: it is really small and it keeps most of the features of the bigger ESP32 options. It is available as kit starting from 5$ with a footprint of 52x21mm.
Compared with the Arduino Nano 33 BLE, the ESP32-PICO-D4 is considerably cheaper (starting from 5$, average 8$ vs 17',5€), it offers WiFi and more Flash (4Mb vs 1Mb), though the Nano 33 footprint is smaller (45x18mm).