It is an Arduino compatible board (hardware ... usual nRF24L01 2.4GHz radio), one power & user LED and finally a reset button. There are two power rails on the board which can be split (5v ...

Arduino has a library for quickly and easily setting up a simple web server on an ESP8622-based board, and [Tomaž] found that power consumption on an ESP-01 can be reduced a considerable amount ...