Easy to use, installed for my aging parents . The app is easy to use and the device itself is easy enough to operate. My parents are 81 and 77 years old and have not had issues with it. I am able to check on it remotely if they are having issues and this has been helpful.
The thermostat is awesome in my opinion. I own a two story home and the original thermostat location is in the dining area on main level and the bedrooms are all on 2nd floor. I also purchased two of the remote sensors and installed them in the bedrooms so that when we are sleeping or upstairs the thermostat on the main level will average the temperature or the sensors upstairs will take priority to achieve the desired temperature you set.
For me this product was very easy to install because I upgraded from a T4 to a T9. I have not have any issues with the T9 and I like the geofencing and being able to control the temperature from my cell.
Great thermostat to use with or without the other temperature sensors that can be used in conjunction with it. Can control thermostat using app as well.