The Notion sensor sticks to your door, wall, or ceiling. It'll sense when the door opens, when the alarm sounds, when the temperature spikes, or if the water leaks.
For $220, you can buy a three-pack of sensors with the necessary bridge to connect them to the cloud.
Here's Notion's bridge. Find a central location to plug it in.
The sensors run on a coin battery that should last one to two years.
Setup is pretty simple, and you can choose what you want your sensor to monitor.
Once you're up and running, you can check on each sensor via the app and customize notifications.
Notion sent notifications quickly whenever the door opened.
It uses probes on the bottom of the sensor to detect water.
Though it looks unassuming, one simple Notion sensor can do a lot.