Today Robinhood is opening up its zero-commission stock trading iOS app to everyone.

The company’s initial app launch was something of a limited release. Only a select number of people were able to get access to the app and everyone else was directed to a waitlist. Since then the company says it has on-boarded “hundreds of thousands of users,” and the waitlist has accumulated up to one million requests, according to founder Vlad Tenev.

Robinhood first released an app on iOS in 2013, but it was a social investing platform. Seven months later, the company made a sharp turn toward fee-free trading with no minimum investment. The brokerage app sells stock, options, and corporate bonds predominately to millennials.

The company’s average user age is 26.5 and 90 percent of the apps’ users are under 40, according to Robinhood. Both Tenev and cofounder Baiju Bhatt say Robinhood is geared toward helping young people develop good investing habits. The apps lets people play around with buying and selling stocks and monitor their portfolio.

In case you’re wondering, watching your stock grow and decline is more addictive than watching your Twitter following — and more instantly gratifying in some cases. It’s also shockingly simple. Once your Robinhood account is equipped with cash, buying stock is a simple touch of the button.

Robinhood, at this stage, isn’t making recommendations for stocks — though it does have a running feed of the most popular stocks of the day. So, you’ll have to do some outside research before making that first purchase. Or not — you can just test the waters and purchase $15 of random stock.

But users will find that after initially discovering the app and getting comfortable with buying stock, questions may emerge, such as, what are their investment goals? It’s questions like these that Bhatt and Tenev hope to stoke their user base into thinking about.

“Some people just want to watch that money grow until retirement,” says Bhatt. But, whatever your desired outcome, he says, when you start young, it’s easier to weather the storm of market fluctuations.

It’s worth noting that though you can purchase any amount of stock on Robinhood, Bhatt and Tenev indicate that the lowest amount anyone is actually investing through the app is around $400.

And while most trading is free, not all of it is. For instance, trades on foreign stocks come at a price. Robinhood also offers paid services, like trading with funds borrowed against your portfolio (known as margin lending) — though this is still in beta.

Already the industry is chock-full of social investment platforms and digital trading tools from E-Trade, Charles Schwab, and others, but Robinhood thinks that it can win the day by targeting the roughly 86 million millennials in the U.S.

Expect to see an Android app from Robinhood later this year.

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