It’s official: as a nation, we’re increasingly mad for smartphones.

According to the results of a new study conducted by the Pew Internet Project, 83 percent of all American adults own a cell phone, and among those, 42 percent of them have smartphones. What this translates to is that more than one-third of American adults – 35 percent – own smartphones today.

While these numbers are of all Americans overall, smartphone ownership is even higher in several several demographic groups: people with high incomes and secondary education, non-whites (black and Hispanic) and people under the age of 45.

These are astonishing numbers when you consider how young the smartphone is. Writes Cecilia Kang of the Washington Post today, “It’s been four years since the introduction of the iPhone and rival devices that run Google’s Android software. In that time, the devices have turned much of America into an always-on, Internet-on-the-go society.”

Additionally, the study found that eighty-seven percent of smartphone owners report using the devices to access the Internet or e-mail and 68 percent do so on a daily basis. Most interesting, about one quarter of smartphone users report that they use their phones as the primary means of access the Internet. While many of these individuals have other sources of online access at home, roughly one third of these “cell mostly” internet users lack a high-speed home broadband connection, reported the studies’ authors.

The study was conducted during April and May via a national telephone survey of 2,277 adults in both English and Spanish. 1,522 interviews were conducted by landline phone, and 755 interviews were conducted by cell phone.

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