About one third of young people ages 10 to 17 say that they “often” or “always” hide their online activities from their parents, according to a 2012 study by McAfee called The Secret Online Lives of Teens. They may be minimizing screens when you walk in the room, deleting content, clearing their browser history, or—one you may not be aware of—using a secret app to hide content. Many versions of these secret apps made for securely housing photos or messages exist.

Titania Jordan, chief parenting officer of Bark.us, an internet safety solution to keep kids and teens safe online, says parents should handle these apps in three ways:

1. Spot-check your child’s device. Look for anything that seems suspicious, like a second calculator app, since one of the popular secret apps is titled “Secret Calculator” and looks like a calculator when opened.
2. Sign up for a parental control monitoring app. “Bark alerts parents to new apps that are downloaded on their child’s phone and has resources on suspicious apps,” says Jordan.
3. Talk to children about the permanence of things put on the internet. Jordan recommends that parents assure their kids their intention isn’t to pry, but to protect their reputation, future careers, and dreams since anything kids put online could come back to bite them many years later.