The ecobee4 is easily one of the best smart thermostats you can buy, the only questions being compatibility with your house and whether you can justify its hefty price tag.
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For me, at least, the concept of a smart thermostat has had a strange appeal since the launch of the first-generation Nest. It may be because my body heat is out of control —I'm the lunatic who opens the window when it's still jacket weather outside. But I also enjoy gadgets that can save you money, and just the concept of home automation delivering pure comfort when I want it.