Square Inc. SQ, -0.43% CEO Jack Dorsey tweeted Wednesday that "most" users of the company's Square Cash platform now have the ability to buy and sell Bitcoin through it. "We support Bitcoin because we see it as a long-term path towards greater financial access for all," Dorsey wrote. "This is a small step." Square confirmed back in November that it had started letting some of the Square Cash service purchase bitcoin via the platform. Rival Stripe said earlier in January that it would be no longer supporting Bitcoin payments via its service, and trading app Robinhood generated attention last week after it announced that it would start letting users trade Bitcoin and Ethereum on the platform. Square shares are up 2.1% Wednesday and 218% over the past 12 months, whereas the S&P 500 Index SPX, -1.11% is up 24% in that time.