A simple weather station using Arduino + ESP8266 + DH11 to provide sensor values such as temperature and humidity.
Temperature/humidity sensors. ESP8266 + AM2320 with a LiPo charger (under/over voltage protection) and 3.7V 780mAh LiPo battery.
Data from Madrid Air quality sensor using an ESP8266, a SDS011 and a Grove multisensor
Data from air quality device in La Orotava (Tenerife, Canary Islands, Spain)