Nest begins learning as soon as you install it. In a short time, it will automatically be adjusting your temperature based on time of day, or how active the house is. For the first few weeks you may need to adjust the Nest a few degrees when required, but eventually it will learn when you adjust it and will start adjusting itself automatically based on how you manually adjusted it before.
The Nest thermostat looks like a piece of tech from the future. It's fully circular and certainly looks the part of a smart thermostat.
The display takes up the majority of the unit, and makes good use of its LCD display when not in use. It can display an analog or digital clock instead of the temperature if you prefer.
Nest also makes other products, such as it's Nest Cam, and smart smoke detector.
Alexa is the voice assistant in the Amazon Echo line of products, and the Nest thermostat can be fully controlled by Alexa. This is important because Alexa can control devices through 100% hands-free voice support.
IFTTT (IF This Then That) is an ecosystem to itself that allows users to create their own custom recipes based on triggers. For example, if it's expected to be humid, the Nest can automatically lower its setpoint to compensate for it. You can also configure other triggers such as location or time of day to determine when the Nest is on or off.
This version of the Nest includes motion sensors that can detect motion from across the room. Previous generations of Nest could only detect motion up to a meter away, but with this generation of Nest the utility is greatly increased.
Motion sensing is useful, because it will sense when you are at home or if you are away automatically, without needing to adjust the thermostat manually.
The Nest Thermostat is the easiest smart thermostat to install. It comes with the required mini screwdriver, and there's a level built-in to make sure the Nest is installed properly. The included baseplate helps cover up any imperfections left from removing your previous thermostat.
Installation is straightforward, and only takes about 10 minutes.
The Nest has a sensor that can be placed in other parts of the house to control the temperature but the only scheduling it offers for it is by pre-selected blocks of time (morning, evening, etc). If you need the thermostat to use the sensor at night until a specific time in the morning and then use the main thermostat you may not be able to if the time blocks don't fit your personal schedule. Seems like something that can be easily fixed through an app update though.
The Nest has a way to set a schedule by day/time through the app but it's really hard to understand how to navigate the scheduling feature and set the schedule properly.
On the Nest itself, the homeowner rotates the ring on the edge of the Nest as the primary way to interact with it. Most controls will need to be done through the app.
The Nest Thermostat doesn't have any other hardware that integrates into it. That means that it only senses temperature from a single point, which means that there can be cool/hot spots in other rooms where the temperature isn't being taken.
You can configure the Tado thermostat to have one setpoint during the day while you're away at work or sleeping, and another setpoint when you are at home requiring heating.
The UI is similar across the different apps and webpage, which makes it easy to use any other UI if you're familiar with one. It's also laid out very nicely, and provides weather reminders as well.
There is an Android app, an iOS app, and even a Windows Phone app. There is also a web app that lets you control the thermostat from any web browser. This is a thermostat that you won't need to worry about compatibility with.
Based on your location, the Tado thermostat can automatically determine when it needs to be on and when it can stay in idle mode saving power. This location data isn't monitored by a motion sensor - instead it uses your phone's location so that by the time you arrive home it should already be a suitable temperature.
You will need to use the hub, which is another piece of equipment in your house. It also needs to be plugged directly into the router which means one less available port on the router.
The requirement of the hub means that the range is limited, which could mean that the thermostat has connection issues depending on where it's installed (walls or far distances will lessen the signal strength).
Tado suggests you get the wiring done professionally. While it's convenient that there is a conversation between you and Tado to figure things out ahead of time - making sure the installation itself goes well - it's inconvenient that you need to have it set up professionally when the other major thermostats can usually be wired with relative ease.
The thermostat is minimal, and it lacks the functionality of normal thermostats if you want to control it through the physical wall mounted unit. Just about all of the controls will need to be done through the app.
Instead of continuously heating and cooling, this thermostat can use a fan mode instead of full cooling to help preserve power while still providing adequate comfort.
If there was an extreme temperature change, Honeywell lets you know. It can also notify you when it's time to change your air filter. Notifications like these are a nice addition, as it keeps you in the loop about what's going on with your house.
The interface is extremely attractive but also informative. It will tell you the indoor temperature and humidity as well as the outdoor temperature and humidity.
While the UI is very functional, it appears cluttered as it tries to display a bunch of information all on the same display. On the main screen, there are 4 tabs on top, two buttons to adjust the setpoint, and it displays the current indoor temperature as well. On the left it displays current information such as date, time, weather conditions, and the status of the system.
Some will appreciate this layout for its functionality, but others will find it cluttered and not appealing.
In addition to HomeKit, the ecobee3 can hook up with IFTTT (IF This Then That - an automation tool based on custom recopies), Alexa (Amazon's voice activated personal assistant found in it's Echo line of products), Wink (a stand-alone ecosystem) as well as SmartThings (Samsung's smart home ecosystem). This allows integration with a wider variety of smart home products outside of the HomeKit ecosystem.
It's easy to install and configuration is simple and straightforward as long as you have a 5 wire system. If your system lacks the 5th wire (known as the C wire), installation is a bit more tricky.
The dashboard on the Ecobee3 will show how it is adjusting the temperature, the overall average temperature, and any savings you may have made by using a learning thermostat.
There's no limit to the amount of sensors you can add through the home. They can detect motion and can tell when you're not home. It even learns not to confuse "no one at home" vs everyone is asleep.
These remote sensors also help to reduce hot spots and cold spots within your house by sensing temperature differences, which allows the system to correct for this.
The satellite sensor is handy, but it adds another connection point which can disconnect (and based on user reviews, it can do so frequently even when installed within 5 meters of the main thermostat).
If your system lacks the common (C) wire and is only a 4 wire system, you will need to use the included Power Extender Kit (5-wire systems don't require this). Then, additional steps are required depending if your HVAC system has a controller board or not.
All of the functions of your phone can also be done right on the thermostat. If you frequently switch phones, or just prefer hardware controls this is a significant perk.
While most smart thermostats go the full mile when it comes to futuristic design, this Sensi thermostat takes a more traditional approach. Just by looking at it, you wouldn't be able to tell that this is a smart thermostat.
This thermostat doesn't offer any smart learning or automation. While it does allow you to program a schedule into it and adjust the temperature remotely, that's just about the extent of its smarts. It doesn't offer motion sensors or track your location in any way.
Most smart thermostats look the part - they look smart. This one looks just like any regular old thermostat, including the clunky buttons, large physical body and monochrome display.