A new viral app has drawn attention to the fact that Facebook users could be giving huge amounts of information without knowing it.

The app sucks up Facebook users’ personal data when it is used. It takes that information to then present interesting facts about a user — but it can also sell that information on to advertisers.

Meaww’s quizzes include games like “Who is your craziest friend?” and “Which friend gives you positive vibes?” Most are based around picking out certain aspects of a person’s friendships — but to do that it takes information about a user that is then subject to the company’s wide-ranging terms and conditions.

A range of companies exist on Facebook that ask users to sign into their apps and so share personal information. Computer experts have warned users to ensure that they check the information that is being shared when they do so, and don’t use apps that are taking information that they don’t want shared.

The Meaww app requests access to all of users’ public profile information, friends list, email address, timeline posts and photos. Users can choose to turn off all but the profile information option, by clicking through a menu.