I have to thermostats on one system, one for upstairs and one for downstairs. After setting high and low ranges. One thermostat ran the heat, while the other ran th AC. You think they would design an option to not do that. Also, usage history is poor and minimal. Bought a separate $20 thermometer with a better app about temperature history and usage. You would think they would be able to design a better system for as much boasting there is about this thermostat.