Every brand campaign needs to factor in consumers' instant and direct access to more information, more channels and more choice than ever before. Today the fight for customer loyalty is the new frontline in the marketing battle.

They are a long-term investment and achieve their return from retaining profitable customers and increasing their spending. In contrast, Groupon-like programmes attract promiscuous shoppers, whose spend isn't profitable and who quickly switch to a competitor whenever they are offering a better deal.

At a branch of Tesco Extra at the unpromisingly named Gallows Corner, in Romford, Essex, an unusual experiment has taken place. Customers owning smartphones installed with Android OS 2.2 or later were offered the chance to download a prototype app, which syncs their online shopping list, stored in their phones, with a map displaying the optimum route through the aisles to find their groceries.