This is a solid little ESP8266 Arduino board for... well, practically everything. It crams in anything you could possibly want, including wifi and probably a serial connector for the kitchen sink. Or to put it another way: it has 5, count them FIVE, ground connectors.
I'm using it as a central board for a few sensors, including a temperature/humidity sensor so my ancient AC turns on automatically when I'm out of the house and the temperature gets too much for my pets. The animals vouch for this board.