It works as it is advertised. I selected it for its remote sensor functionality, which works as it should. But previously I had a cheap digital thermostat which showed the immediate history of how much a furnace or AC was on for the past week or day. This unit lacks that kind of functionality. Not so much smart.
The thermostat was easy to set up and to add additional sensors. It connected to Wi-Fi easily and the app performs as expected. So far, the system seems to be very stable and reliable with the five additional sensors.
I did a lot of research of the brand names of smart thermostats. I own other products of these other brand names and after all that I chose the T9. I have had it for over a month now and am more than satisfied with the quality and functions. My advice to anyone considering a smart thermostat is to do your homework on what you want and need. If the T9 meets your needs I am confident you will not be sorry. It is cheaper than the brand names but it lacks nothing in performance.