All of the services of the Internet bank can be done without face-to-face contact with customers and without bank branches, a great relief for many ordinary people who just don't have the time to visit lenders during work hours.

People can open their accounts by showing their drivers' licenses or resident registration cards -- South Korea's equivalent to a social security number in the US -- to a bank official via video chat for verification of identity.

K-Bank is open around the clock, offering services ranging from ordinary deposits to loans with more favorable interest rates than the ones provided by brick-and-mortar banks.

Jang said he withdrew some money from his credit line to make a down payment on an apartment worth 700 million won.

"What I like most about the Internet bank is that I can do my personal banking at any time," Jang said. "That makes the Internet bank very appealing to young people, though old people may not like it."

About 40 percent of customers opened accounts between 6 p.m. and 6 a.m. Most customers are in their 30s and 40s, according to K-Bank.

K-Bank -- led by a consortium made up of telecoms giant KT Corp., Woori Bank and 19 other firms -- has so far attracted more than 200,000 customers just two weeks after launching operations.

The development represents ongoing innovation in the banking industry in a way that better serves customers who want to do their banking more quickly and at any time.

Shim Sung-hoon, CEO of K-Bank, struck a chord with customers when he vowed to provide ubiquitous banking services in a country where customers have so far followed the rules set by traditional banks.

"K-Bank will open a new era of banks everywhere based on technology and will be at the forefront of financial innovations by offering convenient and unique services," he claimed.

Visiting offline banks can be a hassle for many people as banks close at about 4 p.m. Some people go to a bank during their lunch break to take care of business, but they usually have to wait in long lines to see a teller.

Reflecting on this, Do Binnali, a 30-year-old office worker, said she is satisfied with the Internet bank as she can open an account quickly without going to a bank branch, something she could not do during normal business hours.

Yim Jong-yong, chairman of the Financial Services Commission, has voiced hopes that K-Bank would bring innovation to the country's financial sector beset by slower growth and slim margins.

The financial regulator has also granted final approval to another Internet-only lender, Kakao Bank, setting the stage for fierce competition in the banking industry.

South Korea's top mobile messenger operator Kakao Corp. is among the major shareholders of Kakao Bank. (Yonhap)