There is perhaps no better illustration for the shifting dynamic between fintech and banks than the partnership between TD Bank Group and Moven.

In April, the Toronto-based bank went live with Moven's MySpend money management tool, making it available to its Canadian customers. Branded as TD Myspend, it is a companion app to the TD mobile banking app and allows users to track their spending habits and receive notifications in real time.

The number of bank and fintech partnerships has been steadily on the rise for the past year or so. What was once perhaps an adversarial relationship has warmed; as banks realize there are ideas coming from outside the industry they should be paying attention to, and fintechs realize the challenge of scaling on their own and see bank partnerships as an opportunity to get their technology in the hands of a ready-made customer base quickly.

"We think it has been a fantastic partnership, and we're very proud to be able to partner with a bank of TD's stature and market position," said Greg Midtbo, who is Moven's chief revenue officer and also serves as the managing director of its enterprise business. "Over 550,000 TD customers are using the app since it launched in April."

Midtbo added that TD Myspend remains in the top 25 most downloaded free apps in Canada, now nearly six months after its release.

In the time after the partnership was announced in December 2014 and before the official launch, Moven and TD hashed out details such as customer experience and the branding of the app, as well as the technology TD would need to invest in to enable the real-time information the Moven app delivers.

Midtbo believes that real-time factor is the key to the success of the service.

"I think the most compelling feature is the continual engagement with customers with the notifications," he said. "Before they even put their card away they get a notification, for example, of how much they spent dining out and how it fits into their monthly budget."

Indeed, those features were among those highlighted by commenters in the iOS App Store. For instance, user Adam-gtr titled a review of TD Myspend as "literally the best app."

It "helps to quickly understanding my spending and to keep me on track," the commenter wrote.

TD did not immediately respond to requests for comment on this story, but the company also appears to be pleased with the adoption. It has noted the growing number of users in its last two quarterly earnings conference calls.

"It is an intuitive tool that has resonated with customers looking for a simpler way to manage their finances," Bharat Masrani, president and chief executive of TD Bank Group, said during a conference call to discuss with investors and analysts in late August. "In May, TD MySpend was rated the number one free app in Canada across all categories, and just four months later, we have more than half a million users."

Also, in an interview with American Banker about data analytics, Theresa McLaughlin, the company's global chief marketing officer, called the app "a great example of how you can take customer data and use it for their benefit."

Midtbo said Moven does anticipate expanding the partnership with TD, which could mean offering new features, or expanding the service to the bank's U.S. customers, though the latter decision is ultimately up to TD, he said.

Moven's embrace of partnerships may seem like an evolution of its stance on the industry. Moven was founded in 2011 by Brett King, who has been a vocal critic of the banking industry's reliance on legacy branch structure and slowness in embracing digitization. King also hosts the Breaking Banks podcast. But Midtbo said Moven is far from being "anti-bank," it simply want to make banking more appealing for all bank customers.

"Getting real-time insights is a very high-demand feature [for consumers] and a difference maker," he said. "We want to put this capability in as many people's hands as possible."

Moven is in the process of building other bank partnerships; the New Zealand-based bank Westpac has incorporated Moven's money management tools into its mobile banking app, for instance. And Midtbo said Moven is looking beyond banks and in discussions with telecommunications companies and retailers in markets where those industries can offer banking services.

"Our strategy is to put these innovative tools in the hands of as many consumers as possible," he said.

While all of these partnerships are taking place outside the U.S., Midtbo said Moven is not averse to engaging in partnerships with American banks, even if that means white-labeling its technology to institutions that could ostensibly compete for customers with Moven's own direct-to-consumer product.

"We don't mind competing with our own banking business, so to speak," he said. "We are a supporter and supplier of banks."

But that doesn't mean Moven is solely shifting to a partnership route; it plans to expand its core business at the same time.

"That's still a primary focus for us," Midtbo said.

With the TD partnership, the company is "conservatively targeting 1 million customers on the platform this year," he said.

"With that growing to multiple millions in 2017 based on two strategies, expansion of our U.S. business and partnerships with banks domestically and around the world," Midtbo added.

One of Moven's early peers in digitally focused banking, Simple, also embraced the partnership route and eventually was acquired by BBVA. But Midtbo said Moven does not have an eye toward an exit strategy currently — whether that be an acquisition or going public — and is still simply focused on scaling its business, through partnerships and acquiring its own new customers.

"There's all sorts of scenarios, but at this stage we are focused on building scale," he said.

Robert Barba contributed to this article.