The legendary archer of Sherwood Forest is taking aim at the stock market. Robinhood is a new trading app that promises users free trades and no account minimums.

That's a big departure from the $7 to $10 fees per trade that other brokers which cater to the masses like E*Trade (ETFC) and Charles Schwab (SCHW) charge. These firms offer discounts from time to time, but only if a customer has a large account or uses other services.

Plenty of people are excited about $0 commission trades on Robinhood. The app is still in beta test phase, but nearly 340,000 people have signed up on the company's website to gain early access.

The startup knew there would be interest, but they didn't expect this kind of reception.

Related: 15 Best financial sites and apps

The roll out process is reminiscent of the early days of Gmail, Gilt Groupe and the Mailbox app: There's an aura of exclusivity, and if you refer more friends, you move up the wait list.

Perhaps it's not a surprise that Robinhood is taking this approach since Google Ventures is one of the company's key backers, and a former Mailbox app employee is now part of Robinhood's 15-person team in Redwood City, California.

In December, the company said it was targeting "early 2014" for launch. Now they plan to open the app up to more people on the wait list in the coming weeks and have it available in app stores later in the summer.

"Rest assured when you use it, it will be unbelievably cool," Baiju Bhatt, one of the co-founders, told CNNMoney.

They have worked hard to make the app easy to use on the go. For example, the home screen changes colors depending upon if the stock market is open or closed.

"Our one design principle was building an interface so it's useful in 15 to 30 second bursts like when you're standing in line waiting to order coffee," Bhatt says.

Robinhood was founded by former Stanford roommates Vladimir Tenev and Bhatt who worked on Wall Street after getting master's degrees in math.

Tenev began trading at age 14. Bhatt is a more recent "convert" and calls his own portfolio "remarkably uninteresting."

Related: E*Trade's new ad campaign: Worse than the baby?

The team made its first trade on March 28, according to the @robinhoodapp Twitter feed. For now, trades are limited to U.S. stocks only.

The company's business model is to make money on margin trading, interest on cash deposits and payment for order flow, a fancy way of saying making money by trading faster or slower than others.

Tenev and Bhatt's job on Wall Street was to build high-frequency trading (HFT) platforms for financial institutions.

"At the time, HFTs were commonly paying a tenth of a penny per trade, which enabled the business model to operate with razor thin margins," Bhatt says. "We had a head scratcher moment where we asked ourselves, 'Why do we pay $10 when we trade our personal accounts?'"

There are skeptics about this approach. Robinhood would need huge volume to make money without any fees. But if the wait list is any indication, there's demand for a lower cost service.

The startup is also exploring ways to partner with other apps by sharing API access and offering premium services.

The founders chose Robinhood as the logo to underscore the spirit of bringing trading and investing to the masses.

"Our name acknowledges that a lot of people get a sense that markets are stacked against them," Bhatt says, noting that he doesn't believe the market's predatory reputation is true.

"But Robinhood is on your side, an 'every man' financial product," he adds.