Robb Gaynor, a co-founder of the Austin, Texas-based mobile app developer Malauzai, said his company occasionally does counts of apps in the Apple and Google apps stores and by his reckoning, the number of credit unions with an app is around 50%. As for MRDC, Meara estimated that roughly 10% of credit unions now offer it.

Alan Bernstein, president of the Burlington, Mass.-based technology CUSO Vertifi agreed that 10% seemed right but he fine-tuned that, saying that looking only at credit unions with assets over $100 million, perhaps 25% now have MRDC.

Apps are becoming a competitive differentiator, said Steve Wilson, who focuses on mobile banking apps for Compuware, a Detroit company that benchmarks technology performance. He noticed that although mobile banking apps were tightly clumped together in terms of abilities a few years ago, big differences are emerging where some apps are much better than others. Consumers are starting to change financial institutions to get the features they want, Wilson added. As a result, credit unions are making their apps richer, more robust and more user-friendly.

At the $407 million Vons Employees Federal Credit Union in El Monte, Calif., Donna Young, EVP and COO, said its mobile banking app, which debuted in 2013, initially had been under contract with one vendor. But the credit union pulled the plug when development stalled. Young then made the decision to decouple the mobile app from online banking.

"Tying our mobile app to our Internet banking would have limited the speed with which we're able to get functionality to members," Young said.

Vons FCU partnered with Malauzai, which offers a mobile platform that operates independently of online banking, according to Young.

"This gave us the options, like mobile remote deposit capture, that we wanted our members to have," she said.

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The $1 billion Achieva Credit Union in Largo, Fla., recently severed a longstanding relationship with its mobile banking provider, in favor of deploying a new solution provided by Plano, Texas-based Alkami Technology, said John Wintermeier, SVP and chief information officer of the credit union.

One important difference is Achieva's new platforms will be seamless in terms of online and mobile banking and the user experience will be very similar across devices, Wintermeier said. The new platform will also have many educational and self-service components, which are key features for members, he added.

The $1 billion Meriwest Credit Union in San Jose, Calif., is using a mobile platform provided by Berkeley, Calif.-based Access Software, said SVP Tony Cortez. Still, his aim is continuous improvement of the member's mobile banking experience. Meriwest recently launched MRDC, and with scant promotion, the credit union saw 1,000 deposits come through in the first month, Cortez said. Members discovered the new tool on their own, he noted.

He also said he has another item on his wish list.

"We want to look at mobile lending, applying for a car loan on the phone, for instance. We believe our members will value that," he said, adding being able to provide a means for members to apply for loans at a car dealership and get quick responses is one goal.

More improvements are in the apps pipeline at the $1.6 billion Truliant Federal Credit Union in Winston Salem, N.C., where Rik Kielbasa, senior vice president, said that despite minimal marketing, there are 26,000 active mobile users who are logging on over 200,000 times a month. Kielbasa said he is on the hunt for tools that bring more timely alerts to the members' mobile devices.

"It's about giving people the right information at the right time," said Kielbasa who stressed that the credit union did not want to annoy members, making this a fine line. "The right alerts will give members a sense of assurance that we are looking out for them."

Meanwhile, the development of mobile apps continues to spread. At Brookfield, Wis.-based Fiserv, Scott Hess, vice president, talked about tools that will leverage a phone's geo-location knowledge with fraud prevention. Fueling this new offering is that the mobile phone tends to always know where it is and most users always have theirs nearby.

With those assumptions in mind, Hess suggested alerts that, for instance, would tell a credit union member whose phone is in Houston that there is an attempt to use a registered credit card to buy a $1,000 flat-screen TV in Phoenix. An alert could be fired off in seconds, which would be plenty of time for that member to short-circuit the transaction, he explained.

Hess also talked about work inside Fiserv to build a secure chat channel that would let credit union members talk face-to-face with credit union employees using smartphone technology. He said Fiserv will need to know that this channel will be valuable before digging deeper.

However, mobile banking apps still have one big hurdle to clear before they can can evolve.

"We have to prepare for mobile-first and mobile-only consumers," said Karishma Anand, director of product management at Digital Insight in Menlo Park, Calif.

That may be easier said than done.

Traditionally, mobile banking has been parasitic on online banking. Generally, new payees cannot be added via the mobile device; rather, they must be added online.

Also, accounts typically cannot be opened on mobile devices. With the growth of mobile usage, those limitations have to be lifted.

"It is important for credit unions to think about this customer segment," Anand said. "This is where the future is."