Jack Dorsey Twitter Co-Founder Jack Dorsey Launches New Bluetooth-Based Chat App 5 months ago Jack Dorsey, a co-founder of Twitter, unveiled Bitchat, a new encrypted messaging app, on Sunday. Bluetooth mesh networks are used… Jack Dorsey resigns from Twitter’s board of directors 4 years ago The career of former Twitter CEO Jack Dorsey has come to an end. Dorsey resigned from Twitter's board of directors…