Handheld devices and mini-computers attached to trolleys and baskets can direct shoppers around stores, inform them what&'s on special offer, and calculate spend as they go along. Alan Townsend at ­Wincor ­Nixdorf says that at one end of the scale the Waitrose hand-held scanner for self-payment is the most basic kind of PDA. This recognises a loyalty card and totals up a customer&'s bill as they scan purchases. At the other end of the scale, the rubberised tablet laptop used by member shoppers in Metro&'s Future Store is highly sophisticated. It can pull up a user&'s typical shopping list, direct them around the store and show details of promotions.
"It would be too costly for fast-turnover superstores to offer customers the Metro-style PDAs, but in the future there will be something in between," says Townsend.