Facebook is now offering some mobile app users a wireless-networking app without first disclosing that it's owned by Facebook, or that it collects information for the social networking company.

The app, Onavo Protect, provides users with a virtual private network, or VPN. Typically, a VPN cloaks the user's identity and adds other security features, making it a more secure way to get online, particularly when using public Wi-Fi networks.

Yet the Onavo app also tracks data that it shares with Facebook and others, "including the applications installed on your device, your use of those applications, the websites you visit and the amount of data you use," according to its own privacy policies.

Facebook can use that data to track what users do online even when they're not on one of its websites. The company could also find out how apps made by its rivals, such as Snap and Twitter, are being used.

Facebook, which bought the Israeli security company in 2013, now points to its software in a tab in its mobile app marked "Protect."

Yet a user would have to go to the Onavo website, or expand the "description" link on the Apple App Store and read all the way to the bottom, in order to learn that it's owned by Facebook and shares data with its parent company.

The update was previously reported by TechCrunch.

Here's the promotion for the app.