Of the 1.3 billion people who live in India, more than 100 million of whom are using digital payment apps each day, only about 20 million today invest in mutual funds and stocks. An Indian startup that is betting on changing that figure by courting millennials has just received a big backing.

Groww, a Bangalore-based startup, said today it has raised $21.4 million in a Series B financing round that was led by U.S.-based VC firm Ribbit Capital. Existing investors Sequoia India and Y Combinator also participated in the round, said the two-year-old startup that has raised about $29 million to date.

Groww allows users to invest in mutual funds, including systematic investment planning (SIP) and equity-linked savings. The app, which maintains a very simplified user interface to make it easier for its largely millennial customer base to comprehend the investment world, offers every fund that is currently available in India.

Lalit Keshre, co-founder and CEO of Groww, told TechCrunch in an interview earlier this week that the market of mutual funds is increasingly widening in India and the startup is hoping to accelerate its growth with the fresh capital. Other than that, he plans to double Groww’s headcount to 200 in the coming months.

Groww has amassed about 2.5 million registered users, two-thirds of whom are first-time investors, Keshre said. Groww is currently free to use and does not charge any commission on transactions. The startup eventually plans to offer a paid service as it looks to monetize its user base, but Keshre declined to share a timeline on how soon that would happen.

Groww will also soon begin to offer the ability to purchase stocks from its eponymous app, said Keshre, a former executive at Flipkart who co-founded Groww with three other Flipkart colleagues (Harsh Jain, Neeraj Singh and Ishan Bansal).

In a statement, Micky Malka, founder of Ribbit Capital, said, “We backed the Groww team because we believe in their mission. They have built the most trusted product in this space and are on the path to create a category-defining product.”

Ribbit Capital has made a number of investments in India in recent months. Last month, it invested in Cred, a startup that is trying to improve the financial behavior of credit card holders, and BharatPe, a payments solution for businesses.

In recent years, a number of startups such as INDWealth and Cube Wealth have emerged in India to offer wealth management platforms to the country’s growing internet population. Many established financial firms such as Paytm have also expanded their offerings to include investments in mutual funds.

Ashish Agarwal, a principal partner at Sequoia Capital India, said, “Investment products such as mutual funds and stocks were traditionally sold offline through financial advisors, who were mis-incentivized to sell high-commission products. Groww is taking a refreshing approach with a zero-commission mobile first model, enabling investors to make their own investment choices through a slick and easy user interface.”