Smart thermostat
In 2011, Nest Labs developed the Nest Learning Thermostat. The Nest Thermostat attempted to reduce home energy consumption by addressing the problems with programmable thermostats through the use of better technology. This new technology included the implementation of sensors, algorithms, machine learning, and cloud computing. These technologies learn the behaviors and preferences of the occupants, and adjust the temperature up or down to make the occupant comfortable when they are home and to save energy when they are away. Additionally, the Nest Thermostat connects to the home Wi-Fi. This allows users to change the temperature, adjust the schedule, and check energy usage from a smartphone or laptop. All of these features were part of Nest's goal to create an easy to use thermostat that saves users energy and money.
Humidistat
A humidistat is an electronic device analogous to a thermostat but which responds to relative humidity, not temperature. Humidistats are used in a number of devices including dehumidifiers, humidifiers, and microwave ovens. In humidifiers and dehumidifiers the humidistat is used where constant relative humidity conditions need to be maintained such as a refrigerator, greenhouse, or climate-controlled warehouse. When adjusting the controls in these applications the humidistat would be what is being set. In microwaves they are used in conjunction with "smart cooking" one-button features such as those for microwave popcorn. Humidistats employ hygrometers but are not the same. A humidistat has the functionality of a switch and is not just a measuring instrument like a hygrometer is.