The report pinned the growth on the emerging expectation of being always connected and reachable. In other words, it's as much a social and psychological phenomenon as a technical one. That's turning out to be true even for the gadget phobic, and those "who count pennies," the latter of whom increasingly view the smartphone as a job search tool.

"The social norm is that you should respond within a couple of hours, if not immediately," said David E. Meyer, a professor of psychology at the University of Michigan, in the article. "If you don't, it is assumed you are out to lunch mentally, out of it socially, or don't like the person who sent the e-mail." The article goes on to suggest a parallel between smartphones today and e-mail a decade ago, noting how "at some point in the early 1990s" it became socially unacceptable not to have an e-mail address.