When Scott Fitzsimones turned 13, he got an iPhone, set up accounts for Facebook and Pandora and went on an apps downloading spree. At the same time, the new teenager lost many protections over his privacy online.

The games he plays know his location at any given moment through the phone’s GPS technology. He has entered his parents’ credit card number to buy apps, and iTunes has his family’s e-mail address and everyone’s full names. Facebook knows his birth date and the school he attends.

At an age when his parents won’t let him go to the mall alone and in an era when he would never open up to a stranger, Fitzsimones, who lives in Phoenix, already has a growing dossier accumulating on the Web. And while Congress has passed laws to protect the youngest of Internet users from sharing much information about themselves, once those children become teens, the same privacy rules no longer apply.

“It’s the Wild West for teens when it comes to privacy online,” said Kathryn Montgomery, a privacy advocate and communications professor at American University.

The federal government has a history of regulating media to protect children under age 12. Examples are the 1998 children’s Internet privacy law and television advertising limits that were set for broadcasters and cable networks in 1990. And recent problems with Internet privacy and security — such as last week’s breaches at Sony’s online gaming network — have led to renewed calls for regulations to protect consumers. For the first time, the White House has called for Internet privacy rules.

But experts on adolescent development say youths between 13 and 18 deserve special attention. Reps. Edward J. Markey (D-Mass.) and Joe Barton (R-Tex.) said last week they are working on a bill to limit the collection of personal information about teens and prevent targeted marketing to them.

Adolescents are among the most voracious and precocious users of new mobile Internet services, constantly making grown-up decisions with grown-up consequences, experts say. But, according to Montgomery, “Their ability to make decisions is still forming and clearly different from that of adults.”

‘I never say no’

With few restraints, teens are creating digital records that also shape their reputations offline. All the status updates, tweets and check-ins to specific locations can be reviewed by prospective employers, insurance companies and colleges.

Web firms say sensitive data can be collected only with permission and that parents can set controls on phones and desktop computers to help keep teens out of the public eye. But for teens like Fitzsimones, the opportunities to share information online are so frequent and routine that they hardly even stop to think about them.

The first time he was asked to share his location on the game Pocket God, the seventh-grader paused for a moment to consider why the company would want to know his whereabouts.

But he feared that if he didn’t agree, his experience on the app would be limited, and Fitzsimones wanted to get started on his cartoon pygmy ad­ven­ture on Oog Island. So he tapped “okay,” feeling comfort in the masses; his friends, after all, were using the app and never complained.

Since then, such decisions have been easier. He automatically agreed when Angry Birds, Pandora and other apps asked to track his location.

“I never say no. It’s more annoying than anything when they ask, but I’m used to it now,” said Fitzsimones, now 14, who writes blogforteens.com.

Such decisions are often done under stressful conditions and without enough information about the risks involved, privacy advocates say. Social pressures play out on the Internet, and teens are constantly tested on how much they are willing to expose of themselves in order to play games and participate in social networks, advocates say.

Bolt Creative, which runs Pocket God, said its social networking partner, Open Feint, gets the location data so users can see how their scores rank among people within their vicinity.

Chief executive Dave Castelnuovo said location data is only collected voluntarily. Making too much of a fuss about privacy could turn off users, he said.

“At the end of the day, we’re in the entertainment business and we’re a small team at that. We only have 5 seconds to engage a user once they open our game otherwise we lose that customer,” Catelnuovo wrote in an e-mailed response. “All customers have access to the privacy policy for Open Feint but if we were to present them with additional warnings, cautions and terms and conditions in a form that is impossible to ignore or misunderstand, it will end up ruining the experience that they paid for.”

That perspective concerns privacy and adolescent development experts, who say numerous studies show that teenagers can be more impulsive online.

A 2009 paper by neurobiologists and marketing experts at the University of California at Irvine reported that teens were more susceptible than adults to online advertising and take greater risks with their information online. If a group of friends is meeting for a movie at the AMC Theatre in downtown D.C., for instance, a teen who badly wants to join may send out notice through a public status update — without thinking about the risks of disclosing that information to anyone who might be on a social networking site.

Brain development

The prefrontal cortext, the part of the brain that makes planned and rational decisions, doesn’t fully develop until the 30s, according to the UC Irvine report, co­authored by Frances Leslie, a professor of pharmacology and neurobiology. “Whereas adults rely on a sophisticated interplay between multiple brain structures to make risk-return trade-offs, this is simply unavailable to adolescents,” she and her co-authors wrote in “Adolescents’ Psychological and Neurobiological Development: Implications for Digital Marketing.”

Hemu Nigam, a security expert and former chief privacy officer for My Space, says that means companies should be making their privacy settings for teens tighter by default. “We as parents can to a degree protect our teens from bad content, but we can’t protect them from their own conduct,” Nigam said.

The new challenge in teen privacy involves mobile phones, which are used by six out of 10 teens. Nearly all of those users send text messages and exchange pictures, according to the Pew American Internet and Life project. Three out of 10 teens access the Internet on smartphones.

On phones, privacy policies are often unclear. The Federal Trade Commission said it is investigating one app company that explains its privacy policy only after 152 screen clicks from a mobile device.

About a half of smartphone users read app privacy policies, according to a recent study by industry-funded privacy group Truste. Privacy advocates estimate the numbers are lower for teens.

Up to parents

So parents like Jordan Glicksman’s set rules. He could download only teen-appropriate games on his iPod Touch. They forbade him from giving out personal information like his home address.

But the 14-year-old regularly agrees to location requests from games and Facebook’s Places program. He admits he’s never read through a privacy policy and doesn’t know how much information about him is out there on the open Web.

Glicksman, who is temporarily living in Israel, got swept up in a policy change that made his Facebook profile more widely available. He started getting “friend” requests from adult strangers. Stories he shared about sports and his status updates were public. “I don’t know how that happened, and it was creepy,” he said.

But it hasn’t slowed him down; he doesn’t give it much thought when he checks in a few times a day to his Facebook app and plays games.

Revelations that Apple and Google may have logged the locations of mobile users has brought new attention to Internet privacy from lawmakers, who will question the two companies about their geo-locational collection at a hearing this week.

Foursquare and Gowalla, two popular location-based services, have built a business out of users broadcasting their locations online so that companies can push local coupons and retail suggestions. Both companies set 13 as the minimum age for users.

Foursquare co-founder Naveen Selvadurai said parental controls can help teens opt out of certain services. They don’t track users’ movements, and location is only detected by voluntary “check-ins,” he said.

But he said the firm didn’t consider special protections for teens.

“With a lot of these things, we will figure things out as we go along,” Selvadurai said in an interview. “We are still a younger service, and most of the policies are trying to catch up with things people are doing.”