Thirty-one-year-old Erica Bayne, like most of her generation, lives a lot of her life online. She has a Facebook, Gmail and Instagram. She takes selfies. She checks sports scores.

She just doesn’t have an actual Internet connection, in direct contrast to pretty much every online generation that came before.

Bayne, you see, is one of nearly 17 million Americans who only access the Internet through the data plan on their smartphones. And that statistic could — perhaps even should — change the way advocates, local governments and federal agencies address the stubborn issue of the digital divide.

According to a report released last week by the Pew Research Center, 64 percent of U.S. adults currently own the selfie-snapping, Snapchat-sending things. But a surprising chunk of Americans need their smartphones for way more than Snapchats and selfies: 10 percent do not have any home Internet access besides their smartphone’s data plan, and 15 percent say they’d have a hard time getting online without their phone.

Bayne, who has been smartphone-only for the past five years, is a pretty representative example. The receptionist grew up with Internet at her parents’ house in Johnson City, a village on the border between New York and Pennsylvania. But when she moved into her own place, she didn’t subscribe: Even a modest Internet package in her area runs $35 to $50.

“If Internet got cheaper, or if I got a raise, I would definitely get it,” she said. “But it’s been five years, and it hasn’t become a hassle yet.”

Cost is, predictably, one of the primary factors steering people away from hefty broadband subscriptions. Per Pew, the overwhelming majority of smartphone-users pay less than $100 for a monthly smartphone plan. It’s worth noting that the smartphone-dependent tend to have lower incomes and education levels than their more connected peers; they’re generally young, often minorities, and concentrated more in cities and rural areas than the suburbs in between.

But cost alone doesn’t explain the rise of the smartphone-dependent. There’s also an accessibility issue at play: Huge swaths of the country still don’t have broadband access at all, due to low consumer density or the expense of building infrastructure. Western Massachusetts alone has more than 40 “digital dead zones,” towns where home Internet subscribers can only get slow, expensive satellite or dial-up. Susan McCaffrey, a retiree in one of those towns, does indeed have dial-up at home — but most days, she relies on her phone’s 3G or LTE signal.

Some of her neighbors aren’t so lucky. They only get access at the local library — many communities’ long-time answer to the public Internet problem — and the library is only open 35 hours a week. On Mondays, a day the library usually doesn’t open at all, McCaffrey volunteers there so other people can log in.

“Volunteers do that for the community every week, so that people don’t have to work outside the building in their cars,” McCaffrey said. “That gets trying, especially in New England winters.”

It’s only going to get more trying, in Massachusetts and elsewhere. A recent survey of librarians, conducted by the American Library Association, found that few believe public facilities are prepared “to handle the bandwidth loads in the coming years.”

On top of that, smartphones are only getting more advanced: They’re far more like little computers these days than their names would suggest. Tech writers even wonder from time to time whether smartphones will “kill” off the PC market. (A December 2014 report by the research firm Gartner said yes.)

All of this poses an interesting policy question, if your mind works that way: Could smartphones close the digital divide better than traditional stopgaps — think literacy training, free public Internet, infrastructure expansions — can?

The Federal Communications Commission does, after all, subsidize landline and basic cellphone service for low-income consumers already; that program is called Lifeline, and it’s been around since the Reagan days.

A lot has changed since the Reagan era, though. To complete a job search in 2015, you need an e-mail address and a word processor and a account — not, you know, a decrepit flip phone. You could provide those services by expanding broadband access, which is the traditional, and indeed current, approach. (Lifeline, for instance, just concluded a series of pilot programs to test the value of Internet subsidies, with formal recommendations expected in 2015.)

But maybe you could provide those services via smartphone, too. After all, Pew found, people do just about everything on their phones: research medical conditions, check bank accounts, look up government services, apply to jobs. In 2011, the tech site 2machines profiled a homeless man who relied on his iPhone to check public transit schedules and call shelters.

Many advocates oppose the idea that smartphones should replace computers as a matter of public policy, given the limitations of wireless bandwidth and a six-inch screen. But there are also pragmatists like Jot Carpenter, of the Cellular Telecommunications and Internet Association, who argue that even spotty smartphone-Internet is better than no Internet at all.

Bayne, the 31-year-old from New York, comes down in the middle on this debate.

“I don’t have many challenges using the Internet on my phone,” she said. But what about paying bills? Writing long e-mails? Playing Google Pac-Man?

“Oh, well,” Bayne adds, “I go to Barnes & Noble for that.”

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