Mobile internet use is surging.

We’ve expected for a while now that our mobile devices would become an “everything hub” (a long-term trend we spotlighted in our 2009 forecast), providing services from finance to fitness tracking. But in the U.S., the trend is only just coming into mass adoption. Recent Pew research shows that more Americans now own smartphones than basic phones; as of February, 46 percent owned some kind of smartphone, up from 35 percent in May 2011. At the same time, use of tablets—a device that’s just two years old—is zooming. As this chart shows, Forrester expects usage to nearly double this year, to around 51 million Americans.

All this means that mobile Internet use is set to grow substantially, according to Forrester, which forecasts that by 2016 more than 150 million Americans will be browsing the Web on their phones, up from around 111 million this year, and that 87 million people will be able to access the mobile Web via tablet. Forrester expects that, with mobile Internet usage growing rapidly both in frequency and engagement, mobile marketing spend will increase at a compound annual growth rate of 38 percent between 2011 and 2016. For brands, mobile marketing opens up the ability to engage consumers wherever they are throughout the day, on a variety of devices.

For more on some of the potential here for brands, see our Tablet Checklist and our report on 10 Ways Marketers Are Using the Second Screen.