Around 3337 Android apps have been improperly collecting data on children, according to new research.

The researchers from the International Computer Science Institute used an automated testing method to examine 5,855 apps on Google Play Store and found that the more than half of them were potentially violating Children’s Online Privacy Protection Act (COPPA), a U.S law which forbids data collection for children under the age of 13.

About 1100 of these apps were found to be sharing user’s personal information such as name, phone numbers and email addresses to third parties.

Around 440 apps shared the collected information without using “reasonable security measures.”

And a more shocking finding was that 256 of the apps collected the contact and location data of under-13 children without the permission of parents.

1177 of 1,280 apps tied up with Facebook were not properly using social media platform’s flags to limit their use to under-13 kids.

Around 1100 apps were found to be sharing kids’ personal information such as name, phone numbers and email addresses to third parties.

“Given the number of children’s apps and a complex third-party ecosystem, analysis at scale is important to properly understand the privacy landscape,” the study says.

“Although we cannot know the true number of children’s apps in the Play Store, we believe that our results are representative given that the apps that we examined represent the most popular free ones.”

2,281 apps were appeared to be violating Google’s terms of service that prohibits apps from sharing persistent identifying information to the same destination as Android Advertising ID.

The researchers said it was up to Federal Trade Commission (FTC) to actually determine whether these apps are violating the law and decide their fate.

A Google spokesman wasn’t immediately available to comment on the matter.

The researchers were unable to evaluate apps running on iPhone and iPads due to lack of access to Apple’s iOS data.