(CNN) -- Are you reading this article on your cell phone? If so, you're part of the new mobile internet mainstream.
According to a report published Wednesday by the Pew Internet and American Life Project, Mobile Access 2010, in the past year 38 percent of U.S. cell phone users accessed the internet from their phones. That's a huge jump from last year, when 25 percent of U.S. cell phone users reported mobile internet use.
So how many people is that?
According to Comscore, by the end of April 234 million Americans aged 13 and over were mobile phone subscribers. So, based on Pew's estimate, nearly 89 million people in the U.S. have used the mobile internet in the past year -- close to one third of the total current U.S. population.
Pew also found that 53 percent of Americans who use their phones to go online do so at least once per day. That's more than 47 million daily mobile internet users in the U.S.
It's likely that some of this growth is due to the fast-growing popularity of smartphones. However, according to Forrester Research, by the end of 2009 only 17 percent of U.S. mobile subscribers owned smartphones.
So it's likely that most U.S. mobile internet users are going online not from smartphones, but from simpler, less costly and more limited "feature phones." It's true that feature phones are getting more sophisticated -- but they're still a relatively challenging tool for browsing the Web. So people who go online from a typical feature phone probably have a pretty strong desire to be online.
Pew also noted that African-Americans and Hispanics are leading the charge for the growth use of nonvoice mobile data functions. In all, 46 percent of non-Hispanic blacks and 51 percent of English-speaking Hispanics reported using their phones for internet access, compared with 33 percent of non-Hispanic white Americans.
Furthermore, 18 percent of African-Americans, 16 percent of English-speaking Hispanics and 10 percent of whites are "cell-only wireless users" -- which means their sole access to the internet, e-mail or instant messaging is via their phones.
Age matters. About 65 percent of U.S. cell phone users ages 18-29 go online from their phones, compared with 43 percent of those aged 30-49.
Class matters, too. Pew notes that 46 percent of Americans earning less than $30,000 per year have some kind of wireless internet access -- mostly via a blend of Wi-Fi-enabled laptops and cell phones.
Also, 17 percent of Americans in this lowest income range report being cell-only wireless users. Among Americans who did not finish high school, 38 percent have wireless net access and 20 percent report being cell-only wireless users.
Those numbers may sound low compared with the 80 percent of Americans earning more than $75,000 per year, and 76 percent of U.S. college graduates, who report having some kind of wireless net access.
But personally, I'm encouraged that internet access is within the reach of people with limited means -- and that many people on the bottom of the economic ladder are using the tools already in their hands to cross the digital divide.
The opinions expressed in this post are solely those of Amy Gahran.