The Ecobee3 can be controlled by the on-device touch-screen, the ecobee3 iPhone app, and now also with the Apple Watch. I have to admit, even though it's limited, it's also absolutely amazing. The idea that I can monitor and control the climate in my house from the kitchen table, from bed, from the back porch, or from far away is something straight out of science fiction.
The Ecobee3 watch app tells you the current temperature and the temperature it's supposed to be. Those will always be slightly different, but knowing both you can adjust if and as needed. There are also buttons for the Ecobee3 and the remote sensor.
Force touch options include Fan on, Fan Auto, Home, or Away. Again, it's just the essentials, but it's incredibly convenient to have those essentials always available and right on your wrist.