Robin Swanson isn't shy about looking through her daughter's e-mails or Facebook page.

Her biggest concern is online predators, but she's also worried about sexting, cyberbullying and what's being said on social networking sites. "It's just unbelievable what's going on out there," said the St. Louis Park mom. "You can't be naive these days."

While she's upfront with her 14-year-old daughter about what she's doing, she wouldn't hesitate to resort to high-tech snooping behind her daughter's back if she felt it was necessary. "I would not be above it, because my daughter's safety comes first, whether she's on the Internet or out and about."

Swanson's not alone.

Parents who are finding themselves outgunned by tech-savvy tweens and teens are looking for ways stay on top of what their kids are doing online. It's daunting for parents, who grew up when snooping was a matter of picking up the other phone line to listen in or finding where a diary had been hidden. Now, a growing number of devices -- including phones and laptops -- let their children access the Internet anywhere, anytime. So, tech companies are responding by developing a growing arsenal of spy gear -- aimed at parents -- that's cheaper and easier to use.

Taser International (yes, the zap-the-bad-guys company) will soon be making available a program called Protector that focuses on family safety. Parents will be able to route their child's text messages, images and e-mails to their phone first, allowing them to block inappropriate messages, if necessary. Its Safe Driver package, available later this year, will allow parents to program their child's phone so they can't text or talk while the car is running. (It still allows emergency calls, such as to 911, to go through.)

And if the child is texting at the dinner table or when visiting Grandma? Parents can push a "Family Time" button that shuts down the phone.

But the verdict is still out on whether parents should go to such extremes to snoop and, if they do, whether they should let their teens know what they're up to.

The companies that sell these devices advise a covert approach.

"If you tell your teens that you're checking out their cell phones, they'll get a $20 disposable cell," said Todd Morris, CEO of Brickhouse Security in New York, which sells surveillance equipment. "If you tell your teen that you're putting a GPS tracker on the car, they'll just leave the car in the parking lot and go with their friends in their car. And all of a sudden, your kid who is smart enough to not drink and drive decided to get in a car with someone who might not be."

Family experts, on the other hand, say parents are better off being upfront.

"I would tell my kids: 'I'm not going to be following you around like a detective, but I'm going to check in from time to time,'" said David Walsh, author of a book on teenage development. "Then the kids know that. And that in itself can be something that helps them manage their own behavior."

A new world

Everyone agrees on two things. Teens need different levels of supervision depending on their track record and maturity level. And parents have good reason to be concerned.

"Back in the day, if you flashed your boobs and someone took a photo, it was only a matter of how many people saw that photo," said Linda Criddle, president of the Safe Internet Alliance. "Now, that image can be sent out for everyone to see and live on forever."

Stories about sexting, cyberbullying and Internet predators are enough to make any parent's skin crawl. A survey recently cited by Criddle's group suggests that one in three teens have taken part in sexting (sending and receiving sexual images and text), and that one in four think it's part of normal teen life.

As the concern grows, so do the sales of tracking devices. Brickhouse Security said its Home and Family division is its fastest-growing. According to Morris, the top three items requested by parents are a Cell Phone Spy that lets parents read deleted text messages, the Stealth iBot Computer Spy that lets them track what's being done on the computer and a GPS tracker for the car.

"When we first started selling GPS tracking devices, it was mostly to law enforcement and they were $900 each," he said. "Now you can get one for $100 and anyone who knows how to use Google maps can use it."

Just this week, AOL announced its Safe Social product that lets parents monitor their child's social networking sites, report on their activity and alert them to any red flags.

How much is too much?

How much monitoring a kid needs varies widely, but the best approach seems to be to start early.

For example, when a tween gets a cell phone, parents should tell their child that they'll be doing "spot checks" to monitor activity. Once the parents can see that it's being used properly, those checks should be less frequent and eventually be dropped altogether, Walsh said. If the child resists or inappropriate material is found, parents have every reason to carry through with the predetermined consequences and to continue monitoring, he said.

Bill Doherty, a professor of family social science at the University of Minnesota, said adolescents need zones of privacy so they can develop as autonomous people.

"If you monitor too heavily, it becomes prying and invasions of privacy." On the other hand, he said, parents need to be astute. "One of the boys in the Columbine killings had banned his parents from his room and he was building weapons in there."

Doherty's advice to parents is to move toward more intrusive monitoring if kids show they can't handle lower levels of it.

"If your kid is breaking curfew, not telling you about friends, shutting down the text message immediately when you walk into the room, kids lying to you, those are danger signs" that signal that parents should ramp up their involvement.

But, he said, it's crucial to be honest, because sneaking around just replicates the child's behavior and defines both sides of the relationship with evasiveness.

"You should not sneak. You should always let them know," he said. "If the kid is sneaking around, you don't want the parents sneaking around."

Walsh said parents of teens have a responsibility to keep track of what their kids are doing, but it's natural for those parents to loosen up as the kids mature.

"I don't want to assume that my son or daughter will be able to handle all the situations they get into, and it's my job to do what I can," he said. "As kids get older, there's only so much I can do."

Suzanne Ziegler • 612-673-1707