Other channels are said by some to be reaching their saturation point. However, mobile banking may get closer to that point sooner than most. A recent Federal Reserve study forecasts the channel to hit 50% adoption in a little more than six years, compared with more than 15 years for ATMs and more than 20 years for online banking.

Saturation just means the end of the steep growth curve, not the channel's popularity. In fact, mobile banking is moving from de novo to de facto. Some analysts have seen it go from a tool for techies to a delivery mode for banking for millions of people who transact their lives on smartphones and other mobile devices.

The ability to offer the so-called triple play – text banking, mobile browser and banking by app – is no longer necessarily something to brag about, some experts say.

"Nobody really cares that much now," Sievers said. "At the end of the day, you have to have all those just to be competitive."

Because the only constant is change, that equation, too, is morphing.

"If anything goes away, it'll probably be text," Sievers said. "You don't need text for smartphones. It's the least used of the modes now and the text platforms are merging into what really are push platforms anyway, so SMS definitely has a diminishing life expectancy."

As for the other two bases in the triple play, Sievers said he sees much more intense usage of apps compared with the mobile Web browser. He also sees much more development including the need for the Web browser to continue until the day that smartphones are locked into just having apps.

Tablet adoption dominated hardware work in 2012 and Sievers said he is expecting continued growth. Meanwhile, software interest may remain particularly strong in remote deposit capture and security.

"The biggest deal in 2011 was probably the interest in mobile deposit, particularly at credit unions, and that's continuing," Sievers said. "We're seeing a lot of interest in person-to-person money movement and things like that, too."

Sievers said financial institutions and providers can't spend enough on security.

"We invest a ton of money in it. We have people that run tests inside the company, people who run tests outside the company. It's our goal to keep our stuff safe and secure and working well."

Looking ahead, Sievers said, he sees tablets as being particularly disruptive, especially to online banking.

"I see a world where mobile and tablet dominate the majority of out-of-branch transactions," Sievers predicted.

His confidence in the industry and his own company is apparently shared by some well-heeled investors. In December, mFoundry said it had received $18 million in growth capital from a group led by MasterCard Inc. that also included Intel Capital, FIS and Motorola Mobility.

The company already had a working relationship with FIS, a major player in credit union card, payments and core processing, in the development of mobile services. The additional money will be used to fund the development of new payments-related products and services targeted at both financial institutions and mobile network operators.

"The opportunity in mobile financial services is enormous," Sievers said. "There are many other related opportunities that we believe can add significant incremental value to our company."