DIY heads-up speedo for £1.49

The heads-up display (HUD) technology originally developed for pilots and eventually offered as an expensive optional extra by luxury car makers is now available as an app for iPhones or Windows Mobile devices.

The device is mounted on the car’s dashboard and the apps use the GPS function to calculate and display the speed on the underside of the windscreen. Displaying a mirror image on the screen ensures the speed renders the right way round on the windscreen.

A spokesperson for the Environmental Transport Association (ETA): “Heads-up displays technology has moved well beyond displaying only speed to include thermal imaging and collision avoidance, but even a simple HUD speedometer can allow a driver to monitor their speed without taking their eyes off the road ahead.”

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