said by Kearnstd:
How does it determine if people are home? I only ask this because I know that it has a motion sensor but a majority of thermostats are located in hallways and cannot see the normally occupied rooms, In fact many homes they are located in the hallway for the bedrooms meaning it might not see motion for a good chunk of a day.
It essentially has a motion detector, but you can also override it.
The technique is that you teach it over some time and it memorizes and analyzes your patterns.
Also, you can program it remotely over the web.