(Reuters) -Robinhood beat Wall Street expectations for second-quarter earnings on Wednesday, as interest in meme stocks and cryptocurrencies soared, and said it continued to gain retail trading market share from rivals. The app, typically associated with mom-and-pop investors, saw a surge in trading volumes as meme-stock influencer Keith Gill returned to social media and reignited interest in the highly shorted shares of videogame retailer GameStop. Robinhood's transaction-based revenue surged 69% to $327 million in the quarter.