My upstairs neighbors have flooded their bathrooms twice since moving into my current apartment.

The first time it happened was when a bathtub overflowed three floors above me, damaging my ceiling and leaving a wide brown stain behind. The second time it happened, an entirely different neighbor forgot he left his faucet on. I could hear the water rushing through the walls and watched the paint on my ceiling bubble with moisture.

Needless to say, I’m now frequently worrying about leaks – and fires, and burglars, and basically every manner of tragedy that can befall an apartment.

So when I had the opportunity to try out Notion – a sensor that can detect open doors and windows, temperature, and even leaks – I wondered whether it would reduce my apartment anxieties and keep me informed of how my home is doing even when I’m not there.

Here's what it was like:


The Notion sensor is a tiny round disk, not much smaller than a hockey puck. I used three of them, which all went in different rooms in my apartment: on my front door, near a smoke alarm, and in the bathroom.

Foto: source Notion

The starter kit that I used costs $219 for three sensors and a bridge. A kit with five sensors costs $299, and any additional sensors cost $49 each.


The sensors work thanks to this bridge, which plugs into a central outlet in your home and connects to your WiFi.

Foto: source Notion

You'll need an app to make Notion work. Once you place the sensors around your home, you can name them in the app and let the app know what you want each sensor to track.

Foto: source Notion

The sensor on the floor of my bathroom is in charge of checking for leaks. It sits next to my toilet and alerts me if it senses any standing water.

Foto: source Notion

I also have one on my front door, so I'm alerted any time the door opens. That sensor is checking the temperature, too.

Foto: source Notion

The sensor in my living room is tasked with making sure my smoke alarm is on and functioning. While most smoke alarms already let you know when the battery is running low, having the sensor is an added layer of security.

Foto: source Notion

One warning: These sensors stick to surfaces with tape that's verysticky. I tried to move one after I'd already placed it and it took the paint off my wall.


The Notion app serves as the dashboard for all your sensors. You can open the app anytime to check up on the conditions in your house or learn the current temperature. By having the sensors activated, I learned that my apartment is typically way too warm.

Foto: source Notion

Once you enable push notifications, Notion will send you an alert every time one its sensors is activated. While it can be annoying to get an alert any time my door opens, it's also comforting. If my door opens when neither my roommate nor I are home, I know about it immediately.

Foto: source Notion

But it can also be a little alarmist. One day, it told me an alarm was detected in my apartment, which I initially took to mean that my smoke alarm had gone off. What it really meant was that the sensor had found my smoke alarm and everything was working as it should.


Notion is incredibly well-designed and subtle. But the bridge and sensors only come in white for now, so they look best on white walls and doors. Either way, they're so small that you'll quickly forget they're there. Seriously: Try to spot the sensor in this photo.

Foto: source Notion

After a week with my Notion sensors turned on, I began to feel like they were a part of my home rather than an invasive tech gadget. I liked the feeling of security I had and the ability to check in on things from afar. I even got used to the comforting ding of my phone every time my door opened.

Foto: source Notion

The sensors might not be for everyone, but they could be incredibly useful for larger homes. If you have a gun safe or a liquor cabinet you don't want children accessing, you can place a sensor on the door. If you have a side door or a window that isn't as secure as you'd like, you'll know as soon as it's opened.

Foto: source Notion

Out of all the smart home gadgets on the market, Notion is one of the simplest — and that's a good thing.

Foto: source Notion

While it will be capable of doing more someday, like detecting lights or sticking to propane tanks, Notion doesn't overwhelm you with information or make you feel like you're being spied on. After using it for a week, I felt like it was giving me just enough information to keep my home safe and secure.

You can learn more about Notion on the company's website.