Two-thirds of U.S. adults now use at least one mobile media device such as a smartphone or tablet, and they’re the kind of people marketers want to reach—they skew more educated and higher-income than people who don’t own those devices, according to a survey by the Donald W. Reynolds Journalism Institute at the University of Missouri. And, happily for purveyors of print, they haven’t abandoned newspapers and newsmagazines in droves.