Temperature Monitor with ESP8266
anistor @ instructables.com has build an ESP8266 based temperature monitor system using DS18B20 sensor.
This project will help you create a temperature monitor using an ESP8266 SoC and a temperature sensor (DS18B20) with next capabilities:
Send an email if temperature goes under a threshold
Monitor temperature and set threshold from a mobile App
Temperature Monitor with ESP8266 – [Link]