'We're bringing the best of the PIX payment system in Brazil to Nu Colombia,' says David Vélez.

David Vélez, the Colombian founder and CEO of Nubank in Brazil, the fastest-growing and most successful digital bank in the Western Hemisphere, announced that his banking model is being developed with investments in countries such as South Africa, Indonesia, the Philippines, Pakistan and India , which have large populations and are experiencing good levels of economic growth.

(Read more: How to register your Bre-B system key to transfer money instantly)

Vélez believed that in this way, such diverse countries will be able to develop the Nu model, which has grown exponentially in 12 years.

The executive stated that the process for all individuals to register their keys in accounts with financial institutions, for the implementation of the Bre-B immediate payment system, is the beginning of a reduction in the use of cash in the Colombian economy.

He noted that using cash is very costly due to the informality it generates. "If you save and keep it under your mattress, no one will pay you interest. When you digitize it in accounts like Nu Colombia's, we pay them a high rate that will encourage them to save," he said.

The digital banker pointed out that having physical money doesn't register it anywhere, and that no one gives credit to someone selling an arepa or an avocado on a street corner. However, if they carry out that or another informal activity with a digital account, they will be eligible for credit, and that will improve the mobility of businesses and families.

He emphasized that the use of cash will begin to decline with the Bre-B platform, which will be officially launched in September and will represent a paradigm shift, as it will bring access to credit and savings.

He said a person must register a key for each account and recommended using email, phone number, or a combination of numbers, letters, and symbols.

However, he warned that, as happened in Brazil when the PIX payment system went live, "it's possible that there will be cases of fraud, although there are good tools to try to minimize the impact of cybercrime and protect customers."

(Read more: Bre-B: If you register your cell phone as a key in Nu Colombia, you'll get 4x1,000 back)

Clients on the rise

David Vélez announced that in Colombia , "we've already surpassed 3 million customers and are in the top five in card issuance and deposits, and we're rapidly increasing."

Regarding the Brazilian market with PIX, he revealed that “more than 30% of transactions go through Nu Bank, and much of what we bring to Colombia from that experience translates into us returning 4X1,000 to customers, up to the legal limit, for registering their cell phone key in the Nu account.”

He announced that new developments and products are coming, including credit cards, loyalty programs, and benefits. Nu Colombia has become one of the largest issuers of CDs in the country, and that with its strategy of providing good returns on savings, it has been able to deliver more than $488 billion in returns. He also said that Nubank is the leading investment platform in Brazil, and "we will bring it to Colombia, although with CDs paying good rates, sometimes it's better to have that option than speculate in the stock market."

He recalled that Nubank is a model of digital banking in the West, but it has 9,300 employees, of which 400 are in Colombia and the majority (6,000) in Brazil, Mexico, the United States and Germany.

(More news: Financial user keys will 'open' Bre-B's doors starting this Monday)

More countries are coming with the Nu model

David Vélez, founder and CEO of Nubank, said it's good to have more digital competitors in Colombia, as five large banks currently account for 80% of the business, and with the new competitors, it's positive because there's more competition, meaning more alternatives. He noted that in Brazil, the market is still concentrated despite the arrival of digital entities, as the five largest banks in Brazil went from 80% to 60% of the total business.

"We've invested in South Africa, the Philippines, Indonesia, India, and Pakistan—regions we didn't have much knowledge of, but where we've learned. They're of interest to us, as their economies are growing, and where digital infrastructure is growing, along with instant payment systems."

(Read more: The definitive ABC: this is how Bre-B, Colombia's instant payment system, will work)

The commitment to the 'fintech' model

David Vélez emphasized that Nubank is a fintech company and "we have provided high savings and returns, although some lack value propositions, so not all will be successful, but it is a growing and promising market."

Nubank's CEO warned that high interest rates hamper growth and make credit products that are sources of growth unviable. "We hope interest rates will fall, and that will accelerate the growth of companies like ours and the financial system," Vélez concluded.

(Read more: Banking enters the era of generative AI: more than 70% already use it in Colombia)

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