In summary, the D1 Wi-Fi introduced here is a ESP8266-12E Wi-Fi board, similar to the good old WeMos D1 R1 board that uses the Arduino Uno layout. It’s still very useful as the ESP-12E is a ...

You have an ESP8266 board like the Wemos D1, a Li-Ion battery ... do pushbutton or sensor-driven wakeup, manage WiFi, and even read the battery voltage – all of these are a single line of ...

A lot of people have used ESP8266 to add inexpensive WiFi connectivity to their projects, but [Oscar] decided to take it one step further and program an Arduino over WiFi with the ESP8266.