Smart Thermostats

I have 3 Nest integrated with Smartthings. The Nest Manager app works great and adds lots of functionality (e.g. remote sensor). I have only read good things about Ecobee, so this is probably personal preference which one to pick.

Thermostat integration allows you to be more sophisticated managing them (e.g. keep a thermostat on when a guest is home and you leave, use a temp sensor in another room, only turn on heat on floors where light is on…)