Donna Butler’s 18 year-old daughter hit the road with a friend for a trip that would take about two hours each way. With her daughter’s friend behind the wheel, Donna wasn’t exactly comfortable. But she had a secret weapon: global positioning system, or GPS, enabled in her daughter Danielle’s cell phone.

“I told her to call me when she got there, and after three hours, I hadn’t heard from her, so I was concerned,” says Butler. “So I tried calling her first, and when she didn’t answer, I pulled her up on the computer. She was where she was supposed to be, but the car at that point was clocked at 90 mph.”

That’s right: Through the GPS monitoring system, Donna could tell exactly where Danielle was, what direction she was going in, and exactly how fast.

“The first thing I did was send her a text message that I was not happy with how fast they were going, and if that car exceeded 70 mph again, I would come up there and get her,” says Butler.

GPS monitoring is just one of many secret agent gadgets available to parents these days that lend a hand in both ensuring their kids’ safety and enforcing the rules. Experts give WebMD a look at the hottest spyware technology providing today's parents with a technological edge.

On the Market

Today’s technology allows a parent to keep an eye on their kids almost every second of every day. With GPS-enabled cell phones and little black boxes, parents are well-equipped to monitor every move their children make.

GPS.

“The Wherifone is the world’s smallest cell phone for kids,” says John Cunningham, director of communications for Wherify Wireless. “The value add is not just being able to call your child but also having access to their real-time location. It gives parents a real sense of safety.”

With an embedded GPS system in the phone, parents can access their child’s location, for safety or rule-breaking reasons, via a secure Internet site with a secret password. The web site features a map that pinpoints exactly where their child is, and better yet, it can “breadcrumb.”

“The parent can also do breadcrumbing, which is a series of location requests,” says Cunningham. “So on the map, they can see dots where the child has been, and the direction he’s going in.”

With Wherify, an added feature is that kids can’t rack up huge cell phone bills.

”The phone is set up with designated dial,” says Cunningham. “There are only five buttons on the front, and the parent can program those buttons so they only dial specific numbers.”

Set to hit your local Wal-Mart later this summer, the Wherifone will retail for about $150, with a $20 monthly basic service fee. Nextel also offers a GPS-enabled cell phone, marketed through a company called Teen Arrive Alive.

“Through our program, parents can see where the phone is, if it’s in a moving vehicle, the direction it’s traveling, and it’s speed, which is crucial,” says Jack Church, spokesman for Teen Arrive Alive. “When a parent goes into their password-protected account on the Internet and pulls up a MapQuest map, it has blue dots that represent a two-minute ‘ping’ to the nearest cell tower, representing a history trial of where the kid is, what direction they’re going, and most importantly their speed.”

Developed to keep a watchful eye on young drivers, Teen Arrive Alive couples its phones with a bumper sticker that kids put on their cars. When other drivers on the road see the car speeding, or driving recklessly, they call the number, and the parent can send a message to the phone reminding the kids to slow down.

“I lost a son in a car crash, and when you talk about it from the parents’ perspective, what I hope to get across is to not to take your kids safety for granted,” Church tells WebMD. “Don’t live with that false sense of security that it won’t happen to me or my kid. Get more involved with your kids, especially when it comes to driving.”

As part of the Nextel program, Teen Arrive Alive is a $19.99 add-on service.

“As we start to give them freedom, it’s the cost of peace of mind,” says Church. Black boxes.

Similar to the black boxes found in airplane cockpits, the little black box has made its way into the automobile. Companies like Road Safety International market the technology to parents for about $280 to help them keep a watchful on their kids, while their kids hit the road.

According to the Road Safety International web site, the little black box “monitors how they drive on a second-by-second basis. If they drive too fast, it gives them an audio warning to slow down. If they drive aggressively (hard cornering, hard braking, pedal-to-the-metal starts, etc.), it gives them an audio warning to back-off.

If they follow the warning -- no harm, no foul. If they ignore the warning, the sound turns to a steady loud tone that won't go away until they stop the unsafe action. In addition, their driving is now being graded against a performance standard and reported to you, their parent.

” I’ll Be Watching You"

So you’ve got the car tracked and the phone bugged. Rather than the comforts of home, it’s starting to seem like lockdown. Is building Fort Knox really the way to raise your child?

“With any teenager, you’re trying to establish trust while also trying to make sure they’re not getting into too much trouble,” says Dan Kindlon, PhD, author of "Too Much of a Good Thing: Raising Children of Character in an Indulgent Way." “You’re looking for that shifting line.”

When it comes to gadgets that track their every move, it’s a matter of appropriate use, and knowing when to pull out the big guns.

“I wouldn’t encourage parents to use something like this without probable cause,” says Kindlon, who is a child psychologist at Harvard. “Instead, use it as an option when your kid gets stopped for speeding: You either take the car away, or you let them use it for work and school, but with the monitoring device. It makes more sense than not trusting them from the beginning.”

And communication is key to helping teenagers understand why these devices are necessary.

“You need to talk to your child and say this is why I’m doing it, and maybe it seems unreasonable, but I’m doing it because I’m afraid of what might happen,” says Kindlon. “You have to put on more of a parent hat and say our job is to protect you and the stuff you are doing is scaring us.”

While it may seem like the easy way out, parents shouldn’t even consider tracking their child without letting him or her know.

“It does more damage than good if parents track their kids without the kids knowing it,” says Paul Donahue, PhD, director of Child Development Associates in Scarsdale, N.Y. “If there is demonstrated experimentation with drugs or alcohol, particularly if there is more than one instance of that, then parents have a right to make sure their kids are protected. But I almost never suggest parents do that without letting their kids know.”

Building Trust

With or without these gadgets, parents need to build trusting relationships with their kids, like Donna Butler has with her daughter, Danielle.

“I don’t really spy on her -- that's not what I got the GPS phone for,” says Butler. “Danielle hasn’t given me a reason to distrust her, and kids need their time, too. But in the meantime, they have to obey the rules, and the phone gives me a feeling of security.”

With kids, it’s key to start building trust early on long before they hit their teens, and grow your relationships from there. Communicate with your kids.

“Make sure you have regular opportunities to sit down and communicate with your kids,” says Donahue. “Talk to them about alcohol, drug abuse, and sex. Give your kids an understanding of their limits about their behavior. Kids need to know what is expected of them.”

Let them earn trust.

“Give your kids a sense that they have to earn their trust and privileges,” says Donahue. “Let them earn the right to have a cell phone, or to stay out later.”

Go step by step.

“Whether it's two strikes or three strikes, give your kids a progressive plan,” says Donahue. “If you expect them to call once or twice an evening to check in, and they don’t, give them a verbal warning. Then, let them know that there is a tracking device on the phone, and you will activate it if they aren’t responsible.”

Don’t let robots raise your kids.

“Parents will say, ‘We have this technology in place so we don’t have to worry, and we’re not going to do our job,’” says Kindlon. “Kids have to feel cared for. If you say we can do this with technology and let the robots raise our kids, they’re going to hate you for it. You need to present the device in the context of caring.”

Walk the tightrope.

“Give kids enough latitude to do the things you think they can handle without breaking rules,” Kindlon explains to WebMD. “Give them neither too much, nor too little freedom.”

By Heather Hatfield, reviewed by Ann Edmundson, MD

SOURCES: Donna Butler, Sarasota, Fla. Jack Church, spokesman, Teen Arrive Alive, Bradenton, Fla. John Cunningham, director of communications, Wherify Wireless, Redwood Shores, Calif. Paul Donahue, PhD, director, Child Development Associates, Scarsdale, N.Y. Dan Kindlon, PhD, author, Too Much of a Good Thing: Raising Children of Character in an Indulgent Way; child psychologist, Harvard University, Cambridge, Mass. Road Safety web site.