The Best Smart Home Sensors for Alexa, HomeKit, and SmartThings

When placed around a living space, these low-profile wireless devices are able to detect specific activities, like movement, temperature, or the opening or closing of a door. Then they tell other smart devices how to react—smart lights, plugs, speakers, thermostats, and so on—all in an instant, and without requiring any direct commands or effort from you. Some detect just one activity, while others are multitaskers. Install one and you might solve a single problem—add a bunch and you’re on your way to having a home that runs on autopilot.