The account, known as Finn by Chase, is geared especially to young adults who want to do their transactions on their phones, have no wish to go to branches and say they would like help saving money.

The national offer comes as banks large and small look for ways to use smartphones to compete for customer deposits inexpensively.

Citigroup Inc which has branches in just six U.S. cities, said in March that it will offer digital accounts nationally later this year. Citizens Financial Group Inc a regional bank based in Rhode Island, has said it will launch a national platform in the third quarter.

The banks, however, want to avoid competing solely by paying higher interest rates.

To get customers for Finn, JPMorgan is offering $100 to people who open accounts and complete 10 transactions of certain types, such as sending money to another person or paying a bill.

The incentive is designed to make customers familiar with using the app, said Melissa Feldsher, head of Finn. She believes customers will stick with the accounts after seeing they can automatically make deposits to their savings accounts, such as moving $2 from their checking account every time they spend $5 with the app at a Starbucks coffee shop.

The bank is paying Finn users the same modest rates it pays on deposits to standard Chase accounts, Feldsher said.

The bank is pitching Finn to "digitally centric" users of Apple devices. An app for Android phones is due by year-end.

JPMorgan sees Finn as a supplement to offering standard branch-based accounts. Most people still want to have branches nearby even if they rarely go to them, according to research by consulting firm Novantas.

"This is a way for us to attract more customers by having different products that speak to different people," Feldsher said.

JPMorgan has 5,100 branches in 23 states and plans to open 400 new offices as it moves into new markets, including Washington, Boston and Philadelphia.

Chase is not considering giving credit card rewards as signing bonuses, Feldsher said.

Citigroup executives have said they expect to pitch credit card rewards for digital accounts. Offering high rates of interest would likely attract fickle "hot money" depositors, they have said.

(Reporting by David Henry in New York; Editing by Andrea Ricci)

By David Henry