Reliance Jio had in late December unveiled fourth generation (4G) service for its employees, marking Ambani's return to the telecom sector years after Reliance Group's telecom unit had gone to his younger brother Anil following a split between the two siblings.
"We'll be ready to launch in the second half of 2016. 80 percent of India's population will have high-speed, mobile broadband Internet.
"So 80 percent of the 1.3 billion Indians will have high-speed, mobile Internet. And by 2017, we would cover 90 percent. And by 2018, all of India would be covered by this digital infrastructure," he told CNN's Fareed Zakaria in an interview.
The firm, a unit of Reliance Industries Ltd, has invested close to USD 15 billion in the telecom venture so far. R-Jio holds the highest amount of liberalised (free to use for any service) spectrum among telecom operators, totalling 51.1MHz across the 800MHz, 1,800MHz and 2,300MHz bands. Zakaria travelled from New York to Mumbai to meet Ambani at his residence - Antilia. He is the only person to have interviewed Ambani twice.
Asked about Reliance's massive investment in acquiring airwaves and laying physical infrastructure for offering high-speed Internet services, Ambani said he believed that humanity is at the doorstep of massive change, and "we're just at the beginning of the information and the digital age."
"And in the next 20 years, in a network society, we are going to have change much more than what we have seen in the last hundred years," he said.
Ambani said digitisation will be at the forefront of the digital revolution and India cannot be left behind.
"As we saw in the year 2012-13, India is 150th in the world in mobile broadband penetration as well as quality. And Jio has really been conceived to change this position," he said.
Citing the example of US, where 4G services were launched five years ago, he said major carriers today cover only 75 to 80 percent of the market. "And we would be pretty much doing that in 2016 itself," he said.
RIL chairman and managing director said digital infrastructure is a very good investment.
"For me personally, we made this investment just to make sure that the youth of India, which is still the bulk of India -- India, as you know, is a very young country is empowered, and they have an equal opportunity to not only prosper themselves, but to contribute to this new world.
"And that was really a main reason. And that's why we took very high risks," he said.
The investment with time "now looks like being pretty good even business-wise," he added.