I have mixed thoughts about this thermostat. It is highly programmable which is good if you come and go a lot. It is also good if you are like to sleep in a cooler room or want to reduce heating costs by wearing a sweater. On the other hand, we have a variable speed fan that is controlled by the thermostat but does not appear to be programmable. At first, this fan ran at top speed continually. Even though I did not intend to use the cellphone app, I did install it. Now the fan comes off and on as I had expected. I still can't program the fan but it is controlled.
Though this thermostat provides a wide variety of automation features, the one with the greatest value for us is its simplicity in manually controlling the thermal environment of our living space.
I bought two of these neither of which I was able to get linked. I had 2 heating engineers come and spend 3 hrs. and finally got linked in January. Lost link in August. /talked to Honeywell tech. for 1 hr. 45 min. and never got linked. Not pleased at all with the T-6.