Jack Dorsey runs two multibillion-dollar companies without using a computer

Jack Dorsey, CEO of Twitter and Square, tweeted out a note this afternoon that he had written to his Square colleagues about his CFO, Sarah Friar, who is leaving the company to become the CEO of Nextdoor.

Quartz reporter Dave Gershgorn noticed that Dorsey’s tweet appeared to be a series of iPhone screenshots, which, though not uncommon for anyone tweeting on the go, seems to be a theme for Dorsey.

Ever the muckraker, Gershgorn decided to get to the bottom of this mobile maven’s mystery.

It’s settled then.