Expect mobile payments worldwide to account for more than $900 billion in transactions by 2015. That's the forecast in a new report from analysts at KPMG. According to the report, that means mobile payments globally will nearly double every year for the next three years.

The impetus for the expected expansion of mobile payments will be demand for NFC-enabled devices, the report said, as well as consumers desire for stores that are "always on, always, fast and always accessible."

"Growth in the m-payments marketplace will be driven by customers’ increasing need for convenience and the development of a raft of new applications enabling commerce in the palm of our hands," said David Hodgkinson, senior manager in KPMG’s customer and channel consulting team, in a statement on the report.  

Hodgkinson said that premium SMS dominates mobile payments now, but contactless and cloud-based services will dominate in the future. By 2015, he said, contactless mobile payments are expected to account for 37 precent of the market.

KPMG's report attributes the acceptance of mobile payments as a viable alternative to other methods to increased use of smartphones as well as retailers recognizing their growing importance to consumers. The report said smartphone shipments worldwide last year had increased to nearly 30 percent of all mobile phone sales, a doubling of the previous year's figure. Additionally, the report said, one in five merchants considered mobile payment capabilities to be "important enough to be their ‘main activity or, at least, a key enabler.'"

All of this is good news for companies in mobile payments, but the question of who will emerge as an m-payment winner is still wide open, KPMG said.

"There is certainly scope for collaboration between smartphone manufacturers, telecom companies and retailers but the big, unanswered question revolves around who the customer will trust with their data and their m-cash," said Gerry Penfold, partner within KPMG Risk Consulting. "Battle lines will be drawn around issues such as security, infrastructure and interoperability of devices."

Penfold said consumers will look for speed and security while technology and telecom companies will be concerned about speed to market.

"Clearly, though the winners will be the companies that can provide the richest consumer experience with the greatest convenience," Penfold said.

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