Kini is very reliable. I tested it in a drawer and a cabinet, and it always alerted me when they were opened. It also keeps a log with times listed. While alerts go via the cloud, maker Kinisium says it doesn’t collect data, and you can turn off logging entirely if you prefer. Kini also has a Stasis mode, so you can reverse it and have it alert you when there has been no movement for a set period. This makes it a versatile monitoring device, and you could use this mode to ensure an elderly relative opens their medicine cabinet each day or check what time your dog walker opened a door. Kini is also compatible with IFTTT for automation, and there’s even a webhook integration that can send notifications to a custom URL.

More Motion Sensors

There are loads of other motion sensors that can alert you to motion or presence in an area or room and trigger lighting, but the right one for you depends on your current smart-home setup.

I really like the Eve Motion Sensor, but if you want it to trigger alerts, you need a smart-home hub, and you must set up an automation. It’s a reliable sensor that works indoors or out. I tested it with a Google Home system.

The Aqara FP2 Presence Sensor ($83) has many features, including zonal and multiple person detection, and is compatible with all the major smart-home ecosystems, though it’s not always very accurate at identifying the number of people in the room. The more affordable Aqara FP300 ($50) is a good enough presence detector for most folks and can also track light, temperature, and humidity.

The Switchbot Presence Sensor ($30) is the most affordable sensor I tested and has a similar feature set, but you will need a Switchbot hub if you want alerts, and there’s a lag between it detecting and alerting.

The Philips Hue Outdoor Motion Sensor is excellent, but only if you already have a Hue setup, because it needs a Hue Bridge to connect to. I installed the sensor in my backyard and tested it with the Bridge Pro. It reliably detects people with few false positives. I configured my outdoor sensor to turn on a backyard light strip (not Hue) after sunset and send me a notification when triggered between specific hours (midnight and 6 am) using Google Gemini.

There’s also a Philips Hue Indoor Motion Sensor and a Contact Sensor ($40) for doors and windows. Both are very reliable and can be configured to trigger alerts.

Smart Light Sensing

As an interesting alternative to dedicated motion sensors, you can also use some smart lights for detect presence and motion indoors.

Wiz SpaceSense

If you have a few Wiz lights, you can try SpaceSense, which uses Wi-Fi to detect motion in rooms. I wasn’t that impressed when I tried SpaceSense, but how effectively it works depends on how many Wiz lights you have and where they are located. I was also testing it as a way to automatically turn lights on, and there’s some lag that limits its usefulness on that score. But as a security alert that can tell you when there’s motion in your home when you’re away, it could be very useful. If you already have Wiz lights, you may as well try it, as it doesn’t require a subscription.

Philips Hue MotionAware

Signify is the parent company of Wiz and Philips Hue, and MotionAware is very similar to SpaceSense, but it uses Zigbee, rather than Wi-Fi. Again, how well it works depends on the number of Philips Hue lights you have and their layout. Unfortunately, it does require a subscription if you want to receive alerts. MotionAware can trigger lights at no extra cost, but if you want motion alerts, you must pay $1 per month or $10 for the year. It is also included in Hue Secure subscriptions from $4 per month.

More Security System Alternatives

SimpliSafe

8-Piece Wireless Home Security System

You might consider a modular security system. We like the Simplisafe system, which offers a base station, keypad, and a range of sensors. You can also find modular systems from security stalwarts like ADT and Vivint, and security camera makers like Eufy and Arlo.