Robinhood grabbed our attention for years while it was still on the drawing board. The company succeeded in rocking the financial boat when it launched in Dec 2014 as the first mobile-first, fee-free brokerage, allowing users to trade stocks without commissions or account fees right from your smartphone. Today, the company is announcing partnerships that will let users of financial services StockTwits ( one of Fast Company 's Most Innovative Companies in Finance in 2012), Openfolio, and Quantopian trade directly using Robinhood's platform. (Educational finance company Rubicoin will also integrate Robinhood services when it launches in December.)