That feeling when your mobile-banking app reminded you that the tab from a few drinks with friends had just eaten into your rent money: #buzzkill.

Insert a frowning-face emoji here. Maybe an animated gif of Cinderella sobbing when her wicked stepmother won't let her go to the ball.

Banking doesn't have to be that way, and with the checking and savings app that JPMorgan Chase & Co. (JPM) developed with millennials in mind, it won't be. Finn by Chase, which the largest U.S. lender is rolling out this month in St. Louis, lets users track their spending and savings based on their own goals and preferences -- and their emotions.

The app learns how users feel about their purchases through a tap-and-swipe emoji tool that may give Tinder users a feeling of déjà vu. It also shows them how a debit jibes with the spending plans they programmed into the app previously and enables automatic transfers from checking -- where payroll checks are often deposited directly -- to savings, based on the amount and whether it made the user happy or sad.

Relying on the results of interviews around the country, Finn was developed in just 15 months by the bank's digital team, which works out of a Google-esque office in midtown Manhattan replete with sofas, conversational spaces for brainstorming, games like Foosball and snacks. The process and the result show how the finance industry is modifying traditional ways of doing business to accommodate the unique preferences of the largest generation in U.S. history, the 92 million people born from 1980 to 2000.

Other examples include the Chase Sapphire Reserve card that JPMorgan introduced last year, which offers reward points for shared-service companies like Uber and Airbnb; the upgraded Platinum card from American Express Co. (AXP)  that offers similar features; and the chatbot developed by TD Ameritrade (AMTD)  that lets users buy stock via Facebook (FB) Messenger.

"From a consumer-bank standpoint, almost 60% of our new checking account holders are millennials," Melissa Feldsher, the head of Finn, said in an interview with TheStreet. "They're clearly an important and growing portion of our customers."

 

Finn lets users integrate their spending plans with their emotional reactions to purchases, a feature catering to millennial preferences.
Finn lets users integrate their spending plans with their emotional reactions to purchases, a feature catering to millennial preferences.

Deposit accounts give large banks a significant edge against rivals with narrower business models, and JPMorgan led the nation on that measure as of the end of June, with $1.3 trillion in customer funds, according to the Federal Deposit Insurance Corp. 

That's the base that Finn will build on as the bank rolls it out across the country following its introductory period in St. Louis, where Chase currently has no branches. 

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That attribute it, ironically, makes the city the perfect place to test the features and operational capabilities of what's intended to function as an entirely mobile bank. Finn customers will receive a custom debit card and have access to 29,000 ATMs across the country, including a supplemental network partnership that will give St. Louis users access to cash.

"When we started 15 months ago, we were seeing a growing need from folks who wanted an end-to-end mobile experience," Feldsher said. 

The one-on-one interviews that developers conducted over two-day periods every three weeks showed that those customers, most of them younger, were increasingly stressed by finances. Many reported feeling that budget and banking apps on their mobile devices were judging them. 

"There was such a connection between emotions and finances," Feldsher said. The solution that the bank ultimately co-created with customers gave them a way to analyze that relationship.

A customer might study the app and realize that, for example, "I go to the same place for lunch every day, I get the same salad, and actually, I hate it," Feldsher explained. The obvious question afterward, she added, is "Why am I doing that? I can go somewhere else." 

Finn is debuting on Apple Inc.'s iOS platform and will expand to Google's Android next year. It's supported by a digital account-opening service that lets users sign up from their smartphones, the bank said.

What Finn does for JPMorgan is allow the New York-based lender to develop relationships with millennials at the start of their financial lives that are likely to expand later later, as they buy homes and cars and set up investment accounts.

"People don't tend to change their bank accounts when they're 40 years old,"Feldsher noted. "Our strategy across the entire consumer bank is to be the primary bank for our customers."

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