Back in 2015, when Pew asked Americans of varying ages to "describe" their smartphone, seniors gave overwhelmingly positive answers. He wrote the prescient book "Virtual Addiction" way back in 1999 and is a leading expert on internet addiction, gaming addiction and smartphone addiction. He says that older Americans are just as susceptible to the neurological triggers and traps of addictive behavior. "I have many patients who are in their late 50s and 60s, and a few older," Greenfield says. It's also tempting to dismiss smartphone addiction as a harmless if annoying compulsion.