A robot mower will keep a lawn cut to a consistent height without you touching it, but the right model depends almost entirely on one decision: how it knows where the edge of your lawn is. The three ...

Door sensors detect door position (i.e., open or closed) based on the precise gap between the magnet and the reed switch.

A speed limiter or governor prevents your car from going over a set speed. How do these devices work, and what happens if you ...

Window alarm sensors are an essential part of home security systems, alerting you to unauthorized entries by monitoring window openings, glass breaks and motion. Each window alarm sensor type serves a ...

Dhruv Bhutani has covered the Android ecosystem since 2010, with a focus on smartphones, connected devices, and home networking. His reporting is informed by hands-on experience reviewing hundreds of ...