The Ecobee4 Smart Thermostat has just gone on sale for $199.99 on Amazon. This matches the lowest price this thermostat has ever been, which has only occurred twice before today. The Ecobee4 takes Alexa compatibility further than any other smart thermostat. Not only can you control it through Alexa-enabled devices, like Echos and Fire TVs, but the thermostat itself is an Alexa device that you can talk to and give any Alexa command. Think of it as having an extra Echo Dot mounted on your wall. The Ecobee4 comes with a separate remote sensor so that it monitors the temperature of more than one spot of your home and you can add additional sensors if necessary to make it even more efficient.