Sainsbury's is trialling a free service to allow customers to order shopping on an app and pick it up from stores half an hour later.
The supermarket is offering a faster version of its "Click & Collect" service in its Pimlico store.
Customers will be able to order up to 25 items on Sainsbury's "Chop Chop" app and pick up their shopping after 30 minutes at a desk at the supermarket.
Clodagh Moriarty, director of online at Sainsbury's, said: "The way customers are shopping is changing as they look for faster and more convenient options and we want to continue leading the way in giving them the service they need to shop wherever and whenever they want."
Supermarkets are looking for ways to make it even easier to get their goods to consumers as the UK shopper becomes ever-more demanding with their food shop.
And Amazon has promised to revolutionise the grocery shop by developing a store without check-outs. It is currently trialling the shop in Seattle, but, according to reports, the tech giant is already looking for shop space in London.