BMW iX Flow is the world's first colour-changing car

German carmaker BMW has unveiled the world's first "colour-changing" car at the Consumer Electronics Show in Las Vegas.

The concept car, called the BMW iX Flow, uses electronic ink technology normally found in e-readers to transform the car's exterior into a variety of patterns in gray and white.

When stimulated by electrical signals controlled by a phone app, the material brings different pigments to the surface, causing the car to take on a different shade or design, such as racing stripes.

In the future, the changes would also be controlled by a button on the car's dashboard or perhaps even by hand gestures. No energy is needed to maintain the colour the driver selects.

Though the vehicle displayed at CES could only alternate between gray and white, the technology will be expanded to cover a spectrum of colour, according to BMW.