Text-free apps allow phone users to send messages without a trail on the monthly cell phone bill.
Experts say even the parents who supervise their teens mobile use are getting fooled.
Experts say more teenagers are using texting apps like "Text Free" or "Text Plus," downloaded to smart phones to hide racy text messages.
Eric Hatch from Cell PhoneTechnicians in Chesterfield said, “whether if it’s on your iPhone or IPod, the text free apps can be used with wifi to bypass text messages and even phone calls that you don’t want to show up on your bill. Therefore, a parent or guardian may never notice.”
Other experts said that the only way to make sure your teen is using the phone correctly is to keep an open dialogue with them and if you see a text free app then ask them to delete it.
Click on the video above for Jon Burkett's full report.