This board plugs into just one of the two connectors on the back of the display and can be powered off of the usb port. It came with the example sketch shown in the video and is very well done. Delivery time took around five weeks but was free. I highly recommend this purchase.
Couldn't connect to my wifi whatever I did (using the captive portal), until I re-flashed the firmware. The flashing blue led on the ESP8266 is really distracting, I had to unsolder it. Reflashing the firmware needs quite a number of libraries, which are not all listed in the documentation, but reading the source is enough to find them. The board is fine but would really benefit from mounting holes. I printed myself an enclosure and I'm happy with the final product.