Just like motorists who pay tolls electronically, consumers the world over may soon be paying on-the-go at any shop, using smartphones or tablets. Mobile devices will be our wallets thanks to a technology called "near field communications", or NFC. China is expected to lead mobile payments since it already has the largest network of credit cards.

"In China you have somewhere about 800 million subscribers, so it's a very large market for people to move from paying with your wallet, paying with your card, paying online, paying with your mobile. So it's very natural progression."

France's Gemalto is working with China's UnionPay to build a secure mobile NFC ecosystem. Meanwhile the good old SMS, or text messaging, is spreading as a means of payment, too. Here it's the carrier that bills the transaction. In Barcelona major deals have been reached in this arena. VISA has signed an agreement with Samsung that will allow millions of users to turn their smartphones into contactless payment devices. The big question is whether the banks will participate. Other companies like PayPal think that what should be mobile is the payment terminal. Small businesses could easily get paid on-the-go,' using a smartphone and a portable pocket-size terminal.

"It's a very cheap and affordable way for anyone to accept electronic payments. It goes beyond credit cards because that enables them from their smartphone to check in their store to pay and that's an additional way for the small businesses to accept payments in a really new way."

Mobile money is practical for buyers and sellers, but certainly a gold mine for financial groups eager to get a share of a market that will amount to $300 billion by the year 2020.