Kicking like a 20-year-old baby, the Internet may finally be entering its long-awaited young-adult phase. It's about time: Folks have awaited "Web 2.0" since at least 1999.

Part of Web 2.0 is what some call "The Apps Revolution," app being short for application, a small program you can download into your mobile phone.

In Web 1.0, you sat at a desk, looked at a screen, visited search engines and sites on something called "the Web," and looked at what they had.

In Web 2.0, people are less tethered to desks and moving toward, among other things, the mobile phone to make a customized, self-created universe of Internet uses. The puzzle pieces of this universe are apps, each devoted to one particular activity.

Chris Anderson, editor in chief of Wired, cowrote a much-read article in August titled "The Web Is Dead. Long Live the Internet." The new phase, he wrote, is "driven primarily by the rise of the iPhone model of mobile computing, and it's a world Google can't crawl. . . . And it's the world that consumers are increasingly choosing." People talk directly to people (typical teen: 3,339 texts a month), machines to machines, programs to programs.

Imagine an iPhone with apps that give you almost any radio or TV station that streams on the Internet; let you listen to Phillies games wherever you may be; get on Facebook, Twitter, Skype, or the Web; look up weather, stocks, traffic, or maps; play a Beatles tune; and send and receive e-mail or texts, photos, or videos . . . all on the go. App by app, our own Internet.

"Mobile apps are interesting because they can be so small," says Jonathan Zittrain, a Harvard Law School professor and author of The Future of the Internet and How to Stop It. "People expect to pay little or nothing for them, and perhaps just get a small bit of functionality. Compare with a major software installation on a traditional PC!"

In September, the Pew Research Center's Internet and American Life Project published "The Rise of Apps Culture." Coauthor Kristen Purcell, associate director of research, says, "People call apps a game-changer. They get you a direct connection to the things that are important to you and filter out of a lot of noise. . . . There is definitely a trend toward self-customization, particularly of the way people get their information online."

Sales of smartphones - cellphones that connect to the Internet and run a variety of programs - grew 74 percent in 2010. About one in every five cellphones sold is smart. Of the 235 million U.S. cellphone users, about 45 million are smartphoners. According to market researcher IDC, in February, for the first time, more smartphones were sold worldwide than PCs. And a much-noticed 2009 report by RBC (formerly Royal Bank of Canada) says that by the end of 2011, smartphones will outnumber PCs worldwide. Period.

And folks like apps. In January, the Apple App Store, open since July 2008, hosted its 10 billionth app download.

That doesn't mean people know what to do with their apps. In the Pew survey of 2,252 people 18 and older, 35 percent had apps on their phones, yet only 24 percent used them.

"We have a public education issue here," says Purcell. "People are a little hazy about what an app is. Or even what a smartphone is. About 11 percent didn't know whether their phone had them or not." Seventy percent said they felt overwhelmed by the info online.

Roger Entner, analyst for Recon Analytics, says, "Sure, apps make it very easy to make your own little corner of the Web." But he takes a drier-eyed look. "The real innovation is how apps are packaged and marketed. Some apps do amazing things, but 70 to 80 percent of them are actually just glorified bookmarks," taking you to much-revisited content.

But what of the vaunted "Gold Rush" right now, with thousands of young geniuses flocking to create and market apps? "The Gold Rush made a few millionaires, a lot of rich store owners, and a lot of poor people panning for gold," says Entner. "And in this case, the store owner is Apple." He reports that the typical iPhone app makes $8,700 - over its life.

Zittrain points out that, though liberating, the app world is largely the product of corporate biggies such as Apple and Google, which (especially Apple) have a lot of power to decide what users can and can't do - "and once that's the case, regulators can step in to require the vendor to ban certain things." He worries, as do others, about "centralization of control."

Anderson, of Wired, writes that as long as consumers get what they want, they don't care: "The delirious chaos of the open Web was an adolescent phase subsidized by industrial giants groping their way in a new world. Now they're doing what industrialists do best - finding choke points. And by the looks of it, we're loving it."

Contact staff writer John Timpane at 215-854-4406, jt@phillynews.com, or on Twitter at @jtimpane.