T-Mobile's fee-free Money banking service, officially launched earlier this month, relies on the Minneapolis fintech firm ClickSwitch Holdings Inc. to attract customers from other banks.

The relationship is a turning point for ClickSwitch, which created software to simplify the process of moving a person's direct-deposit and bill-payment information from one bank to another.

The firm in the past two years has signed up more than 300 banks to incorporate its technology into their online services and mobile apps. But most of those firms are small and haven't launched a national marketing campaign in search of customers the way T-Mobile just did for T-Mobile Money.

"We are forecasting T-Mobile to be one of our largest clients," Cale Johnston, chief executive of ClickSwitch, said Monday. "Shortly after their launch we are already experiencing tremendous volume."

He added that T-Mobile is "raising the standard for digital banking across the industry."

A T-Mobile spokesman said via e-mail that it considered various technologies to reduce what the company viewed as customers' "pain points" in banking.

"Direct deposits are one of those pain points," T-Mobile said in a statement. "People have typically had to fill out forms, give them to HR and then wait to have the changes happen. ClickSwitch makes changing direct deposits and allocations between accounts super simple."

With the launch of T-Mobile Money, the nation's No. 3 provider of wireless service is one of the first major tech brands to jump into personal finance. Apple Inc. announced in March that it would offer a credit card later this year.

The smartphone firms are using their brand recognition and existing relationship with consumers, literally in their pockets and purses, to expand into another line of business, as they have with music and movies, for instance. Banking is a juicy target because there's room for competitors to undercut the fees charged, and beat the rates offered, by the existing industry.

In addition to no fees for checking accounts, T-Mobile Money will let customers overdraft their account by up to $50 with no penalty as long as it goes back into the black within 30 days. It will also pay savings account-style interest, offering a 4% annual yield on accounts with a balance of up to $3,000 if a person deposits at least $200 a month into the account.

T-Mobile executives compared T-Mobile Money to products of the nation's biggest banks — Chase, Bank of America and Wells Fargo — when they formally launched it on April 18. "Traditional banks aren't mobile-first, and they're definitely not customer-first," CEO John Legere said in the prepared announcement that day.

T-Mobile didn't charter a bank to provide the service. Instead, it formed a relationship with BankMobile, a unit of Philadelphia-based Customers Bank, to serve as the bank. As a result, T-Mobile Money's checking accounts will be insured by the Federal Deposit Insurance Corp. up to balances of $250,000.