Want to track your child on Facebook? That’s so 2009.

No matter how much time limits parents impose, or how much they track their child’s Facebook timeline or Twitter feeds, experts say nothing beats talking to your children about how everything that goes up on the Web never really goes away – even when software companies promise it does.

First came Friendster, then Myspace. By the time Facebook took over social media, parents had joined the party, too. But the online scene has changed - dramatically, as it turns out - and these days even if you're friends with your own kids on Facebook, it doesn't mean you know what they're doing.

"What sex education used to be, it's now the 'technology talk' we have to have with our kids," said Rebecca Levey, a mother of 10-year-old twin daughters who runs a tween video review site called KidzVuz.com and blogs about technology and education issues.

More than three-fourths of teenagers have a cell phone and use online social networking sites such as Facebook, according to the Pew Research Center's Internet and American Life Project. But Facebook for teens has become a bit like a school-sanctioned prom -- a rite of passage with plenty of adult chaperones -- while newer apps such as Snapchat and Kik Messenger are the much cooler after-party.

Even Facebook acknowledged in a recent regulatory filing with the Securities and Exchange Commission that it was losing younger users: "We believe that some of our users, particularly our younger users, are aware of and actively engaging with other products and services similar to, or as a substitute for, Facebook," the company warned investors in February.

Educators say they have seen kids using their mobile devices to circulate videos of school drug searches to students sending nude images to girlfriends or boyfriends. Most parents, they say, have no idea.

A stay-at-home mom of eight kids in Burke, Va., Eileen Patterson said she used to consider herself fairly tech savvy and frequently spends time on Facebook. But she was shocked to learn her kids could message their friends with just an iPod Touch mp3 player. She counts nine wireless devices in her home and has taken to shutting off her home's Wi-Fi after 9 p.m., but she describes her attempt to keep tabs on her kids' online activity "a war I'm slowly losing every day."

"I find myself throwing up my hands every now and again," Patterson said. "Then I'll see something on TV or read an article in the paper about some horrible thing that happened to some poor child and their family, and then I try to be more vigilant."

Mobile apps refer to the software applications that can be downloaded to a mobile device through an online store such as Apple's iTunes. According to the Federal Trade Commission, there are some 800,000 apps available through Apple and 700,000 apps on Google Play.

Among the most popular mobile apps among kids is Instagram, free software that can digitally enhance photos and post them to your account online. Kids on Instagram whose parents closely monitor their text messages, Facebook posts or emails can also chat with their friends using the service. Their photos can also be shared on other social media sites such as Facebook, which bought Instagram last year.

Then there's Snapchat, among the top 10 free iPhone apps available. Snapchat lets a user send a text, photo or video that purportedly self-destructs within 10 seconds of being opened - or warns a user if the recipient takes steps to quickly capture it for posterity before it disappears.

Kik Messenger also allows unlimited texting for free and effectively offers anonymity to users.

As with anything online, each of these services comes with caveats.

Snapchat acknowledges on its Website that messages aren't guaranteed to disappear: Anyone receiving a text or photo can within 10 seconds capture a "screenshot," taking a photo of their device's screen, and save that image. Video also can be downloaded, although Snapchat says it alerts senders when material is saved.

Instagram is considered tame as long as kids adjust their privacy settings to limit who can see their photos and don't post nudity, which could subject them to child pornography laws. But Levey said many parents don't know their kids are using Instagram until there's trouble - usually when kids post inappropriate photos at parties and these begin to circulate among their social circles.

Parents often hand their kids a mobile device without understanding exactly what it can do, said Dale Harkness, a technology director at Richmond-Burton Community High School in Richmond, Ill. He estimates that even without using social media services, the average high school student probably transmits some 150 texts a day.

"It's not anything that every parent and grandparent hasn't already seen," Harkness said. The problem, he adds, is that actions "get documented, replayed and sent around." He said that students "forget how fast it moves and how far it goes."

A big hurdle for parents is overcoming the idea they are invading their kids' privacy by monitoring online activity, she said. In fact, she said, it can be the kid's first lesson that hardly anything online is private, anyway.

"If they want privacy," she said, "they should write in a journal and hide it under their mattress."

Based on reporting by The Associated Press. 

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