This is a real solid performer. Works better than the T5 thermostat that I also have. Set up and programming were pretty simple. The manual controls are easy so that everyone in my house can simply change the temperature as they need. I use the Honeywell Home app all the time to change the temperature remotely. My only knock is that finding vacation mode was difficult, but I like that you can set it to go back to normal on the day you are expecting to return home.
The integration with my iPhone is seamless. No need to really do anything but create an account and link it to my thermostat. The heat/AC turns off when I leave and turns back on when I am heading home. After a couple days, just forgot it was there as it just seemed to work.