The Nest wi-fi thermostat is created by Tony Fadell, who worked at Apple on the first 18 generations of the iPod and the first three of the iPhone, and the not surprisingly the design of the thermostat is one of the most striking features. The Nest functions very similarly to the Ecobee wi-fi thermostats, but has some features not seen on Ecobee. The one that stands out the most (may not always be practical) is the activity sensor that works with the Auto-away feature. A list of the Nest features can be seen here.You can access the Nest online and control it from your iPhone or Android phone.

Of all the smart thermostats out there, the Nest may have one of the best installation pages; whether you choose to go with a Nest certified installer or install it yourself.In the video "How to save more with Nest" they company highlights 4 key energy saving features:

• Auto-away
• Auto-schedule
• Nest leaf
• Energy history.

You can buy the Nest on their website, Amazon.com, the Apple store, Lowe's and other certified professionals.

When buying the Nest thermostat, make sure you are purchasing the 2nd generation, model number T200577 and not the 1st generation, model number T100577 (unless you review the differences and are fine with the first generation, which you can probably find cheaper like this one on Amazon).