Betterment, an automated investment management service, continues to attract the attention of global investors. 

On Tuesday, the "robo-adviser" announced that it had raised $100 million in a Series E funding round led by Swedish investment firm Kinnevik, with participation from such previous investors as Bessemer Venture Partners, Menlo Ventures, Anthemis Group and Francisco Partners. To date, the startup has raised $205 million, for a total valuation of $700 million.

The company helps customers to manage exchange-traded funds (ETFs) as it provides real-time investment advice. "We're the record keeper and the broker-dealer," said Jon Stein, Betterment's co-founder and CEO.

"Two years ago, there were a lot of people who might have said it was unclear how things were going to shake out in this space. Today, I don't think anyone says that anymore," he adds.

To Stein's point, Betterment has grown its assets under management (AUM) to nearly $4 billion since launching in 2008, with 150,000 total clients. Last year, it rolled out a suite of new investor tools, such as Betterment for Business--a cheap 401(k) feature for business owners--as well as Betterment Institutional in 2014, which provides tools to other financial advisors.

Users pay between 15 and 35 basis points for Betterment (between .15 and .35 percent on their assets under management). For reference, the average cost of a traditional financial advisor in 2016 is 1.35 percent on a $50,000 investment, according to AdvisoryHQ. (Less-affluent investors with less than $100,000 in accounts will typically pay at least 1.3 percent in annual fees.)

What makes Betterment unique, says Stein, is the fact that it keeps its customers "best interests" at heart--rather then peddling its own funds for a commission. And because Betterment has no investment minimum, the solution has become increasingly attractive to younger investors: the average Betterment client is 36. 

The company isn't the only financial technology startup that aims to eliminate the need for a human advisor, though. Wealthfront is another major investment service that has raised nearly $130 million in VC funding to date, and manages about $3 billion in customer assets as of 2014. Still, ask Stein who the competition is, and he's quick to point fingers at the banks.

"A better comparison is [Charles] Schwab and Vanguard," he says. "We're not getting customers from startups, we're getting customers from the big guys, and it's those business models we're looking to turn over." 

There have, of course, been challenges in building out the nascent investment platform. "It gets harder and harder as the company gets bigger," said Stein. "As we scale and as any company scales, you come into this adolescent phase, where you're not quite a mature company but you're no longer an infant startup either."

During Betterment's puberty, and with the fresh infusion of capital, Stein plans to hire "aggressively," adding to his team of 149 employees. This year, he says he'll focus heavily on building out the newer tools; a new feature would allow professional advisors to "put their personal spin on advice," for example. He adds that there's been enormous uptake with the 401(k) product, which launched last September, so he's hoping to create more tools for HR and Benefits this year. 

To be sure, even the major players in the financial industry, including Charles Schwab and Vanguard, are beginning to roll out their own automated investment tools, which could potentially steal business from the upstarts. Yet as Stein puts it: "They struggle a lot with the execution because they're not really tech-focused companies."