In a world of near-zero in terest rates, phone carrier Telefonica SA is starting a new mobile banking service that skips the cash and re wards loyal customers with a currency it has in abundance: data for smartphones.

Telefonica Deutschland, the Spanish carrier's German unit, next week will introduce "O2 Banking," according to two people with knowledge of the information. The more of ten customers use the Master Card included in the deal, the more free wireless data they'll receive. The accounts will be serviced by Fidor Bank AG.

While Telefonica's appli cation will be the first mobile banking service from a phone carrier, others have long offe red banking in the developing world, especially in Africa. Kenya-based Safaricom in 2007 introduced a service called M-Pesa that now handles more than $50 billion in transactions annually .

In Europe, other carriers faced with scant growth in their home markets are exploring similar offerings. Orange SA, which provides financial services in Poland and Africa, bought 65% of the banking unit of Groupama SA in April. It expects to introduce financial services for mobile users in France next year.