Here's how car speedometers calculate how fast your vehicle is going. And here's why they may not always be accurate.

You can use speedometer apps on your Android smartphone to find out the speed of your car, bike, or other vehicle. Speedometer apps tell you the current speed, average speed, over-speed alerts, trip ...

Apple recently revealed a new version of its CarPlay system for vehicles, which include gauges like speedometers. But even Apple, the company that cast aside tradition when it reinvented phones, music ...