 The way smartphones and smart thermostats work is they allow the user to control them from anywhere in the country to make sure that they're getting the highest level of efficiency with their thermostat. An average household spends nearly $2,200 a year on energy bills, half of which go towards heating and cooling empty and unused spaces. Having a smart thermostat in your home can save time, use less energy, which in turn saves you money. Many companies sell them, so shop around for the one that best suits your needs.