People check their mobile phones over 80 times every day, and while that frequency may alarm us as we survey a crowd of people hunched over their phones, it is less disturbing when we look at why and where people use their phones. Most of the time, when we check our mobile devices, we engage them for less than thirty seconds. While we can use our phones most anywhere, research shows that we are most likely to use them at home, in transit, at work, waiting in line, and in a public space. My book, The Procrastination Economy: The Big Business of Downtime, delves into mobile device use and describes the vibrant “procrastination economy” found in those spaces.The procrastination economy is a term I give to efforts by media companies to design mobile apps, platforms, products, and hardware that monetize our in-between moments. My book argues that mobile devices, and our experience of much of the Internet, is determined by the spaces of the procrastination economy. The traditions and behaviors associated with these spaces shape user behavior and media company strategies. For example, Facebook’s 2006 redesign, replaced the personal-profile landing page with “News Feed,” a scrolling timeline that made the social network easier to use while checking in with friends during a break at work. YouTube put their “background playback” functionality behind a subscription paywall because people like listening to streaming video while multitasking on their phones on the commute. Casual games, like Candy Crush, offer short bursts of entertainment ideally suited to filling the time while we wait in line.Film developed in relation to the experience of watching movies in a theater. Television was shaped by the cultural and spatial politics of the domestic sphere. Readers should remember this history as they learn about the spaces of the procrastination economy and the ways mobile devices have amplified activities that were previously marginalized. The office breakroom television, the waiting room pile of magazines, drivetime radio, and the crossword puzzle we did during commercial breaks, are all a part of the procrastination economy. The strategies and assumptions that informed these cultural objects are now shaping our use of smartphones, tablets, and the Internet of Things.