ESP IoT pHAT
The ESP IoT pHAT is an ESP8266 based add-on for the Raspberry Pi. It provides some GPIO and one ADC channel, broken out to use alongside a small prototyping area. Perfect for RPi Zero but works with A+/B+/2 too!
To get the pHAT set up and ready to go you can use the one-line product installer:
curl -sS https://get.pimoroni.com/iotphat | bash