Stock trading app Robinhood has raised $363 mln in a series D funding round in order to expand its crypto trading platform, ‘Robinhood Crypto,’ US-wide, according to a company press releasetoday, May 10.As Fortune reports, the funding makes Robinhood the second most valuable fintech startup in the US, and its current valuation is at $5.6 bln, more than a fourfold increase from last year.DST Global led the recent round, with new investors including Sequoia Capital, Kleiner Perkins, Iconiq Capital and Capital G (the VC arm of Google parent company Alphabet).Over 4 mln users have now opened brokerage accounts with the service, which has been offering a crypto-specific platform since February, currently available in 10 U.S. states.In an interview with Fortune, co-CEO Baiju Bhatt said the company plans to offer “trading in 16 different cryptocurrencies including Bitcoin, Ethereum, Ripple, and Zcash,” and offer a “more favorable cost structure,” with no commissions, than existing platforms.Bhatt also emphasized that Robinhood is already a registered broker-dealer with the Securities and Exchange Commission (SEC), unlike leading US crypto trading platform Coinbase. The latter currently has around 20 mln users, and lists only four cryptocurrencies, according to Fortune.Notwithstanding Robinhood’s aspirations to outstrip its existing rival, both will soon have to contend with major institutional Wall Street players on the verge of entering the Bitcoin trading market. Investment banking giant Goldman Sachs recently announced it will be opening a crypto trading desk “within weeks,” and ICE, the parent company of the New York Stock Exchange, now reportedly plans to offer Bitcoin (BTC) swap contracts, settled in BTC.