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Notion review: Notion’s multitasking sensors are too single-minded

They’re not great at multitasking, and don’t do any one task as well as the competition.

Andrew Gebhart Former senior producer
7 min read

Notion tries to squeeze all the smarts you need to watch over your home into a small white puck. For $220, you get three of those pucks and a bridge that plugs into your wall and connects those sensors to the cloud. You can ask a puck to tell you if your front door is open or closed. You can stick one in the laundry room to watch for leaks or on the ceiling where it will listen for your smoke detector.



The Good

Notion packs a lot of functionality into an unobtrusive sensor -- you can use it as a door monitor, a temperature sensor, a leak detector, or ask it to listen for smoke alarms. You can easily assign and change what you want your sensor to monitor in the app.

The Bad

Notion doesn’t work with any other smart home system, so once it senses something wrong, it can’t do much with that info. It can monitor multiple things at once, but your options are limited by the app and where you need to place the sensors to make them effective.

The Bottom Line

Notion isn’t the best option at any individual task and the way it combines tasks doesn’t actually add much practical use.

Instead of buying a bunch of different specialized sensors to do these same tasks, the Notion sensors adapt to your needs by multitasking. I love the idea of decluttering the smart home, but in practice, Notion doesn't offer any practical advantage over more specialized sensors like the $40 SmartThings Multipurpose Sensor or the $50 Roost Leak Detector. The app limits what senses you can turn on together, and some of the combinations you can enable don't make sense.

At the moment, Notion doesn't work with any other smart home systems either, so if it does detect something wrong, Notion can't do anything other than send you a push notification. Because of that, Notion isn't as good at any individual task as the best specialized devices out there. I'd wait for future updates before investing in Notion, or if you know what you want to monitor, you can take your pick from a crowded field of specialized sensors.

Notion’s multitalented watchdog will monitor your home

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Getting the Notion

I tested the $220 three pack of Notion sensors with a bridge. The $300 package might be the best deal -- you get five sensors with a bridge. Individually, you can buy an additional bridge for $80 and an additional sensor for $50. Head to the company's site to make a purchase. Notion's only available in the US and Canada.

The site also talks about the eight senses of Notion -- temperature, acceleration, natural frequency, light, motion, sound, angular rate and water. In the future, Notion could use all of these senses to their full potential and sense the light levels in your home. It could tell you when your propane tank is almost empty. It could even listen for the doorbell.


Notion packs a lot of smarts into a small sensor. 

Tyler Lizenby/CNET

Right now, those eight senses boil down to four basic options. You can use Notion to monitor when a door opens and closes (including a garage door), Notion will sense temperature, it'll watch for leaks, and it'll listen for smoke or CO alarms.

Setup's pleasingly simple. You need at least one sensor and the bridge to get started. Plug the bridge into any outlet, and you'll see the light at the top start flashing. Create an account via the app, then you'll scan the QR code on the back of each sensor to add them to your account. Each bridge can accommodate up to 15 sensors.

If you have a big house, you might need more than one bridge so all of your sensors are in range -- the bridge had trouble picking up a sensor when I moved it down one floor and over a couple of rooms. Thankfully, you can position the bridge so it doesn't block the adjacent outlet. Get the bridge and the sensors synced, and you can start placing the latter where you need monitoring via the sticky adhesive on the back.


Notion's app walks you through the setup process. 

Screenshots by Andrew Gebhart/CNET

The limits of multitasking

I used my first sensor to monitor the door of the CNET Smart Home. The app asks you to place the sensor above the knob at the top of the door. I wanted this first sensor to multitask as much as it could, so I used the app to try to enable Notion's other senses.

The app stopped me from using it to listen to smoke alarms -- you can't enable that feature on a sensor monitoring a door. You can turn on temperature readings, as well as leak detection. Given the placement of the sensor at the top of the door, that first sensor would have issues detecting leaks. By the time the water level got that high, I'd hope I'd already have noticed a problem.


Hopefully you'd notice a leak by the time it got this high. 

Tyler Lizenby/CNET

Both the $100 Kidde RemoteLync Monitor and the $100 Leeo Smart Alert Nightlight listen for smoke and CO Alarms, and both can listen for alarms anywhere on the floor of a home. A door sensor that also provided this functionality would have been unique and useful. That combination would have made a lot more sense to me than combining leak detection with a door monitor.

I setup my second sensor as a listener, and the app asked me to place the sensor on the ceiling near my detector. Again, I could enable leak detection for some reason, as well as temperature readings.

I suppose the leak detection could catch a drip in your ceiling when it rains, but you'd have to place it in the exact right spot, so you'd already know there was a problem. I used my third sensor as an actual leak detector, and set it up in the laundry room of the smart home, with temperature readings turned on for that sensor as well.


Notion on the ceiling. 

Tyler Lizenby/CNET

Notion can multitask in theory. In practice, you can combine a temperature sensor with any of the other functions, but can't realistically combine anything else.

Testing the Notion

At each individual task, Notion performs admirably. I always received a notification within a few seconds of the front door opening. You can also turn notifications off when you're at home, away, or at night. You can manually tell Notion when you leave, or let it use your phone for geofencing.

In the app, you can tap on your door icon to see a simple log of when the door opened and closed. The leak and sound sensors record a similar log. The temperature sensor actually charts its measurements over the course of the past day, week, and month. You can customize notifications with each enabled sense. So with the temperature sensor, you can put it in your wine cellar, pick an ideal temperature threshold, and have Notion let you know if it ever gets hotter or cooler.


Notion's home page gives an overview. Click on any task for more details. When your alert settings trip, you'll get a push notification and an in-app alert. 

Screenshot by Andrew Gebhart/CNET

The app lets you add and remove functions from each sensor as you please. Even after the initial setup, you're limited in what senses you can use together, but Notion's main advantage over the competition comes if you change your mind about what you want to monitor. You could fairly easily repurpose a door sensor into a flood sensor in the furnace room if you think there might be a problem.

As a flood sensor, Notion picked up water pretty quickly, and the sensor is somewhat water resistant. Notion has two probes on one side of the sensor. When water connects them, it completes a circuit and Notion sends you a push notification. The tech is similar to the other flood sensors we've tested, though some have an option to sound an alarm or interact with your larger smart home to flash the lights.

I also fooled the Notion's flood sensor when I used my finger instead of water to complete the circuit. Plus, Notion's pretty small, so you'll want to be strategic with where you place it if you want it to detect a problem early.


These are the flood-sensing probes on the bottom of Notion. 

Tyler Lizenby/CNET

When I sounded the smoke alarm, Notion responded quickly with a push notification if it was in the same room. Notion's hearing ability did prove more spotty when I moved the sensor a room away. It's understandable that Notion can't hear as far as the Kidde or Leeo monitors -- both of those plug directly into a wall. Notion needs to conserve power since it's running on a battery. Still, because of this limitation, it's less useful as a safety device as it can realistically only listen for one alarm.

I also ran into a strange glitch while testing Notion's listening functionality. The coin cell battery in each Notion sensor is supposed to last a year or two. Mine died within a couple of weeks. According to a company representative, it woke up to listen too frequently, but the problem only affects a small percentage of customers.


I ran into a strange glitch where Notion's battery died quickly. 

Tyler Lizenby/CNET

I haven't been able to replicate the problem on a second sensor yet -- I repurposed the laundry room sensor as a listening device. I did run into another glitch with that sensor, as it looked to have lost all temperature data for a morning, but the charts eventually repopulated after a couple of hours.

The same company representative hinted that the next generation of Notion sensors will be arriving shortly -- hopefully by the end of this calendar year. Glitches aside, Notion functions well enough, but if you're interested in the system, it's worth waiting for the second generation of the product to see if it polishes the edges of the experience and handles multitasking better.

The verdict

Yes, Notion's $50 sensors are multipurpose, but because of where you need to place them, you'll likely only use them for one task at a time. You can turn on leak sensing in your door monitor, but the app asks you to place it in the top corner of your door. If the water level rises that high, I'm pretty sure you'd know something was wrong already.

Getting started with a $220 three-pack of sensors and a bridge isn't a bad deal, but it's a little expensive. Notion does well enough at each individual task you ask it to do, but it fails to separate itself from the multitude of capable smart home sensors you can find with any of the major platforms such as SmartThings, Wink, and Insteon. If you want connected monitoring, I'd pick what you want to monitor and start with a single purpose sensor. Hopefully, the second generation of Notion sensors will follow through on the promise shown by the first gen, but I wouldn't recommend spending $220 on potential.



Score Breakdown

Features 5Usability 6Design 6Performance 7