I installed an Ecobee a couple years back and besides changing the furnace temp from the couch like 2x a year I never use it any differently than I would a normal programmable thermostat. Maybe I'm just a thermostat Luddite but I increasingly feel like these things are a solution looking for a use case. It was cool 5 years ago if you had a Nest but I feel like this particular fad is fading out.
I moved from a standard thermostat to a “smart” thermostat last fall when I installed a central humidifier. I wanted a single device which could control heat, A/C, and humidity, and most advanced thermostats that can do that are contractor-only items (yes, I know they are available online sans warranty).
That left me with aftermarket options from the likes of Ecobee, Nest, and Emerson (Sensi).
Since I don’t prefer the Google ecosystem, I tried Ecobee. I really had high hopes. It put heat, A/C, and humidity control in one box, and could pull outside air temperature and provide automatic humidity adjustment. I loved the data it collected on system temperature and runtime overlayed with outside air temperature. There was one huge problem: its temperature sensor was way too sensitive, and would increase or decrease simply by walking or standing in close proximity to the unit. This would result in temperature swings inside the home caused by erratic system operation (this is with eco+ disabled). I tried many suggestions to fix it, spent hours with tech support, plugged holes in the wall, etc. The temperature reading just remained too unstable to fit within our preferences for system operation.
There were other small indicators that the unit was borne of a technology company and not a company experienced with system controls, which I did not consider to be a positive trait for a device whose primary purpose is to be a system controller.
Ultimately, I returned it and purchased a Sensi Touch. It is a bit less feature-rich, but includes the core functionality I sought and is clearly designed and built to be a system controller. I can still control it from an app or through HomeKit, and it does a much better job of dampening the room temperature readings which I experienced with Ecobee.