When his teenage son ventured into social media, Virginia father Mike Robinson wanted to make sure he could keep tabs on him. Robinson works in IT, so he rigged a surveillance system that works no matter what kind of device either of them is on.

"It's sort of like a version of remote desktop that enables you to run the program kind of silently in the background," Robinson says.

One day, checking in from his iPhone, Robinson discovered that his son had come across an adult meet-up site on Facebook.

"It wasn't that he was ... trying to find people," he says. "He was just trying to look at the pictures that were on those sites, which were pretty explicit."

That prompted a father-son chat about values and relationships.

"From a parental perspective," Robinson says, "I don't think I'd be doing my job unless I was trying to keep track of this type of activity."

Not Like Reading A Diary

"I think it's one more tool that we can use as parents to ensure our children's safety," says Betsy Landers, president of the National PTA.

She says parents are feeling their way, trying to bring up kids responsibly in a digital landscape they didn't grow up in themselves. The old advice — put the computer in a common room and block certain sites — no longer works now that the digital world has gone mobile. And Landers says keeping tabs on what a child does online is not at all like reading a diary.

"It's open to so much exposure," she says. "Predators now can prey on our kids online when they are totally unaware that they're dealing with an adult."

Of course, not everyone's adept enough to set up his own monitoring system like Robinson did. But parents' fears have prompted a booming new market in apps designed to help Mom and Dad stay one step ahead of their child.

Popular software includes apps like uKnowKids, MinorMonitor and Norton Online Family, which can comb through every Facebook post, text, instant message or Google search on a child's device and alert parents to keywords of their choosing. Another app, MamaBear, also promises to notify parents of signs of bullying or inappropriate language and can even alert them if the car their child is in is speeding.

One tech blogger castigated MamaBear as "intrusive," "controlling" and "down right disrespectful" to children. She's not the only one with concerns.

Undermining Trust?

"When parents are engaged in these kind of monitoring activities, they end up being interpreted by their young people as spying," says Lynn Schofield Clark, who has a new book called The Parent App about families in the digital age.

Clark worries that too much monitoring undermines trust between parents and children. And, she says, it can backfire. She found plenty of teens with two Facebook accounts, only one of which Mom or Dad knew about.

"Teenagers are always about trying to create some kind of a space for themselves, where they can interact with their peers apart from supervision," Clark says. "And so they're gonna find ways to do that."

Dave Otto, father of three daughters in Northern Virginia, says he doesn't want his children "feeling like it's normal that I know every word or every thought." But Otto is an information security specialist with the federal government, and he knows all too well about the risks online. He uses a program called Web Watcher, which logs every email, instant message and keystroke. But Otto mainly keeps quiet about what he finds.

"There are things I've seen, where, I kind of slap my head and think, 'Ack!' " he says. "But it was just kids being kids. I can't police that. I don't want to police that."

Mostly, Otto says, the monitoring prompts discussions about the amount of time his kids spend online when they're supposed to be doing homework.

While some worry about intruding on teens' private lives, Kim Kelso of Tampa, Fla., says a monitoring app has meant newfound freedom for her 16-year-old son.

"I just got an alert that my son just arrived home," she told me as we spoke one afternoon on a school day. The MamaBear app had just sent her an automatic message once her son walked in the door at home.

Her son has mild autism, and Kelso says he's prone to getting lost and doesn't always make good decisions. But with her new monitoring ability, she's allowed him to not only get a phone but also join Facebook.

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