And the ESP8266. Not as fancy but it's half the price. I love both the ESP8266 and the ESP32 a ton. They really made wifi projects "cheap" for entry-hobbyists instead of some 70USD wifi shield.

Yes, esp seems to be a great choice in 2019 - more IO, more ram, wifi. Digikey prices for esp8266 start at $ 1.85 https://www.digikey.com/products/en/rf-if-and-rfid/rf-transc... , modules are a dollar more https://www.digikey.com/products/en/rf-if-and-rfid/rf-transc...

I picked up a few ESP01 boards from Aliexpress recently, they're less than $1.50 each. They only have two GPIO pins accessible (and one needs a pull-up resistor to make the ESP8266 boot properly) but for toggling a relay or reading a simple sensor over wifi they're hard to beat. They're even powerful enough to run a basic HTTP server to handle a light web interface for the GPIO.