Smartphones can do so many things. Gauging your speed is one of those things. You may need a speedometer app for many reasons. Runners can use them to gauge their speed. Car enthusiasts can use them ...

If you drive your hot rod, even once in a while, then you depend on all of your gauges to be reliable and accurate. Just a small percentage of miscalibration can result in engine damage or failure, ...

If you've ever modified a car with smaller or larger tires or, perhaps, a different final-drive gear, you've immediately screwed up your speedometer. This is, of course, annoying, but for modern cars ...

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 ...