I have multiple outside cats and they like to wait either on the porch (front) or the grill (back). With winter, we worry that maybe we will miss one and it might freeze. I will be building a IoT enabled platform for the front and back that will alert us to the presence of a cat hat needs in. Plan to use the esp8266 (since I have a few of them).
Main goal is to just use the ESP8266. It has enough power and memory to do what I need.
Also Android app to alert the family (wife, son and myself ) that a cat is in the front or back.