Hungary-based Cellum Group, a provider of mobile payment and technology solutions, announced its newest mobile payment solution for iOS devices with Passbook at Apps World Conference, held today and tomorrow in London.

So far, Apple's Passbook has had only limited payment functionality, finding use mainly for storing loyalty cards, tickets and boarding passes.The new Cellum solution offers the interesting possibility of integrating debit and credit cards into Passbook.

"To our knowledge, this is the first mobile payment solution that can be integrated into Passbook," said Cellum senior vice president Jeff McAllister in a statement.

The next step in the evolution of e-commerce is m-commerce, and that starts with a downloadable commercial application, McAllister said. He called the demo version Cellum presented a breakthrough that unifies mobile payments and ensures bank grade security.

It's the security part that differentiates Cellum's solution. Passbook is based on an open platform, meaning any company can integrate applications. That's great for gaining acceptance from merchants. Retailers such as Target and Starbucks, along with a number of airlines such as American and United, have already begun to work with Passbook. A downside to the open platform, however, is that Passbook does not on its own offer high security standards and therefore hasn't been suitable for highly sensitive bank payment solutions that store bank card details.

Cellum's new solution uses a method the company calls "secret distribution." It's a combination of encryption and cloud services that protects bank card data. Only a portion of the data is encrypted and stored on the device, while the rest of the data is stored on secure servers.

Once the Cellum solution is stored in the Passbook app, the next step in making Passbook into a mobile payment tool is figuring out which technology will transmit that card data at the point of sale. Cellum's solution doesn't specify any technology, but Starbucks is already using barcodes through its app as well as Passbook. Eventually a solution presumably could use any technology, including QR codes or even NFC, if later versions of the iPhone include the technology.

Cellum said its "secret distribution? solution has already been in use by MasterCard Mobile in Hungary for a year, and the company is in negotiations with financial institutions and other companies to use its technology in the U.S. and abroad.

For more stories like this, visit the mobile/virtual wallet research center.