In a few years shops will be different things to different people. Their products, music and lighting could depend on who you are. Even how you are. In some Japanese clothes shops, interactive hangers already detect which dress or pair of jeans you're showing an interest in – and show you videos of what the clothes will look like when you're wearing them, and what other items could complete your look. Firms in the US are testing face recognition software that gauges customers' moods. How long until this is used to create personalised shopping experiences, where the store chooses products to fit the type of day you're having? Smart technology could transform supermarkets too. Sensors in labels will talk to your mobile to tell you how fresh a pint of milk is, which wine goes best with the ingredients in your trolley, or which products contain allergens like peanuts or gluten.