In today’s world, everything is optimized to work directly from your fingertips — your calendar, your security system, and now your thermostat. With a smart thermostat, you can be at work, the grocery store, or a thousand miles away on vacation, and still be able to control your AC unit at the touch of a button. They’re WiFi-enabled, so as long as you have a wireless connection, you have constant access to your HVAC.