Indian consumers are quickly moving online and local banks will have to do more, to ride the digital trend, Kotak said.

"I am excited, but very challenged. I keep wondering at night, will I have a bank the next morning, or will some technology company be doing banking without needing a bank?" he told CNBC.

The founder and executive vice chairman of Kotak Mahindra Bank said technological innovation does offer huge business opportunities for India's banking sector. But it could also change the face of the industry.

If there's one thing that keeps Indian banker Uday Kotak awake at night, it is the threat of disruptive digital technology.

"As long as there is cash and the economy is running, all is well. But as a bank, we'll have to test, experiment, try a hundred different things. A few may work, a few may fail, but we have to experiment and try," he said.

Kotak declines to reveal if he is working with any digital partners, but said he is not against aping successful mobile applications by competitors.

"There's no harm being a copycat. If someone else is doing a good job, copy. It's free. But speed is important," he said.

A self-starter, Kotak founded Kotak Mahindra Finance in the 1980s, when he was in his 20s. The company later became India's first non-banking finance firm to be converted into a bank. Kotak Mahindra now has more than 1,200 branches across India, with almost 40,000 employees, after the successful merger with ING Vysya Bank in April.

Ranked as the 7th richest person in India according to Forbes, with personal assets of over $7 billion, the savvy banker is known for his instincts in recognizing good business opportunities.

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"The trouble with opportunity is, it never announces when it comes. It's only after it's gone, you'd realize that you missed it. Therefore, my strong belief is that when opportunities come knocking, there is something more than the normal 5 senses which tell you this is the way to go. Listen to your instincts at those critical junctures," he said.

Having made his wealth, Kotak's greatest wish is to leave a legacy for future generations.

"In my first trip to the U.S., going around Wall Street, I saw a number of global banks; Goldman Sachs, JP Morgan and Morgan Stanley. They all have one thing in common; all of them are family names. At that stage, I thought, we must work towards creating institutions like these in India. Founders have this challenge, what may start as an individual journey, has to transform into an institutional journey. Effectively, what you create must outlive you," he concluded

For more on Uday Kotak's interview, tune in to Entrepreneur Asia: Power Players on CNBC. The episode will air on May 21, at 5:30pm sin/hk, with repeats over the weekend.