Robinhood Markets, the company behind the popular mobile application known for commission-free equity trades, is introducing free cryptocurrency trading with a coupe of catches.

First, only bitcoin and ethereum will be able commission-free for Robinhood users. Second, the deal is only open to clients in four states – California, Massachusetts, Missouri and Montana.

“Robinhood Financial has rolled out commission-free trading for bitcoin and Ethereum across California, Massachusetts, Missouri and Montana, the company said on Twitter. As CCN previously reported, users will still be responsible for fees charged by the underlying exchanges. But you can’t beat the quick access to funds,” reports CCN.

Related: 3 Steps to Responsible Bitcoin Investing

What is Robinhood?

Robinhood introduced commission-free stock trades three years ago and has since added options and exchange traded funds to its platform. The company introduced trading in bitcoin and ethereum in February. When the company introduced crypto trading, it was unveiled to clients in just five states.

“Robinhood Markets, the company behind the popular stock trading app of the same name, is set to receive a capital injection valuing it at around $5.6 billion,” CNBC reported last month, citing the Wall Street Journal.

After bitcoin, the largest cryptocurrencies are Ethereum, Ripple, Bitcoin Cash and Litecoin. Bitcoin futures debuted on the Cboe in December, followed by a launch on the CME. Nasdaq Inc. is still considering entering the bitcoin futures competition. Market observers previously expected Nasdaq to launch futures on the digital currency this year, perhaps as early as the second quarter.

Related: Looking Ahead to $20,000 Bitcoin

“While traders are limited to trading BTC and ETH, they can access market data on more than a dozen altcoins. Robinhood Crypto offers features like ‘instant access” to funds via deposits or stock sales, which is a streamlined approach that traders are sure to like versus the alternative of waiting for their funds to arrive on other platforms,” according to CCN.

California-based Robinhood generates revenue on fee and subscription models as well interest gained in user accounts.

For more information on the cryptocurrency market, visit our Bitcoin category.