The next gadget I buy to automate my smart home won't be a contact sensor for my doors or even a cheap motion detector. This is the year I'll be upgrading to a presence sensor. This device works by continuously tracking people in a space—it can tell if you plop down on the couch, move to work at your desk, or even hop into bed.
Unlike a motion sensor, which merely detects movement, a presence sensor uses a variety of technology such as radar, infrared, or ultrasonic waves to monitor changes in its surroundings.
