Gadgets & Gizmos: Colour-changing cars, health-monitoring lights & self-cleaning cat litter

Steve Caplin and Simon Rose savour the latest great - and not so great - ideas on display at the annual Consumer Electronics Show, including colour-changing cars, a lightbulb that monitors health, a self-driving tractor, invisible headphones, an autonomous trolley, a camera for identification that attaches to glasses for those with poor eyesight and a self-cleaning cat litter tray that also assesses your moggie's health. Learn more about your ad choices. Visit podcastchoices.com/adchoices