U.S. adults spend two-plus hours a day thumbing on mobile devices The Nexus 7 tablet is demonstrated during a new product introduction by Google at Dogpatch Studios in San Francisco. U.S. adults spend 63 minutes a day on tablet devices, according to a report by the research firm eMarketer. Gary Reyes / MCT / July 24, 2013 By Paresh Dave August 1, 2013, 1:14 p.m. Driven by surge in multitasking and the widening ownership of tablets and smartphones, U.S. adults are expected to spend 2 hours, 21 minutes a day this year on their mobile devices doing things besides making calls. That's the equivalent of about one in every 10 minutes. The estimate, released Thursday by the research firm eMarketer, marks the first time that mobile-device usage will surpass the time devoted to Internet browsing on laptop and desktop computers. When considering people using multiple devices at once, the firm counted both. Since the Apple iPad came out in 2010, the amount of time people spend with their phones or tablets has risen about two hours, or nearly 500%. And the 2013 estimate is about 50 minutes higher than eMarketer's measure from last year. The numbers have been validated in recent days by earnings reports from online companies such as Facebook Inc. and Yelp Inc. They've seen a continuing increase in visitors and ad revenues from mobile apps. People spend about half a day consuming media. More than 80% of that time is spent on computing devices or televisions. The rest is attributed to forms such as newspapers and the radio. Of the mobile device usage, 67 minutes comes from smartphones, 63 minutes from tablets and 11 minutes from feature or so-called dumb phones. More than 60% of U.S. adults have smartphones, according to Nielsen. Tablet ownership is pegged at 34%, according to Pew Research. Now, the question is, where will wearable electronics such as Google Glass and the rumored Apple iWatch fit into next year's report -- mobile devices or a whole new category?