Latest version 3.0.0. Wemos D1 mini is like a "little Arduino with wifi" for a great price. It's based around the ESP8266, has one analog port and 11 digital ports. It's programmed via micro-USB (or remote flash via wifi). You can use it with the Arduino IDE, micropython or NodeMCU.

It runs from 5V or 3.3V. Logic levels are 3.3V for all ports. 

If you use the Arduino IDE, there are a lot of example sketches already provided. This makes life relatively easy to be able to do what you want.