The one-time chief executive of social media giant Twitter and payments platform Square is now focused solely on Block (Square’s new crypto-themed name). Jack Dorsey is perhaps Silicon Valley’s leading Bitcoin evangelist. He’s called the cryptocurrency the “native currency of the internet,” and has worked to bring that about. Before stepping down from Twitter this year, he integrated BTC Lightning payments. His payments app, CashApp, a unit of Block, sees a tremendous amount of bitcoin buying.