We have seen plenty of smart thermostats in the past. The ecobee3 happens to be a WiFi thermostat that helps you control your home heating/cooling system from your iOS device. This HomeKit-connected thermostats is now available through the Apple Store. That means you can control your thermostat using Siri.
The device measures the temperature in multiple rooms to keep you as comfortable as possible. It supports up to 32 sensors. Its Home IQ tech provides free personalized reports and energy savings information. You can get yours for under $250 at this time.