Increasingly, people of the book are also people of the cloud. At the Codex Hackathon, a convention whose participants spend a frenetic weekend designing electronic reading tools, I watch developers line up onstage to pitch book-related projects to potential collaborators and funders. “Uber for books”: a same-day service that would deliver library volumes to your door. “Fitbit for books”: an app that blocks incoming calls and buzzes your phone with reminders to get back to a book. That literary pedometer meets its real-world counterpart in LitCity: “Imagine walking down a city street and feeling that familiar buzz of a push notification. But instead of it being a notification on Twitter or a restaurant recommendation, it’s a beautiful passage from a work of literature with a tie to that place.” I thought back to the nineteenth-century guidebooks that inserted a snippet of Shelley next to their map of the Alps; the book has always been about bringing worlds together.