Some popular Android apps have been sharing data with Facebook without users' permission, a new study has found.
Privacy International, a UK-based campaign group, found that TripAdvisor, Kayak, Skyscanner and MyFitnessPal are just a few of the many Android apps that are sending sensitive user data to Facebook.
In some cases, the apps were sharing private data with the social media giant even if users didn't have a Facebook account.
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Some popular Android apps, like Skyscanner, MyFitnessPal and TripAdvisor, have been sharing data with Facebook without users' knowledge, a new study has found
Privacy International conducted a review of 34 popular Android apps and found that at least 21, or 61 percent, of them began collecting data from users as soon as they opened the app - and before users gave permission to do so.
'This happens whether people have a Facebook account or not, or whether they are logged into Facebook or not,' the firm explained.
When an app is opened, the data that is initially sent typically includes things like the fact that a Facebook SDK (Software Developer Kit) is running.
'This data reveals the fact that a user is using a specific app, every single time that user opens an app,' Privacy International said.
It also reveals information like what kind of device a user is using, the software version running on the device, as well as the screen resolution.
Facebook's SDK is a platform that the firm offers to developers and lets users login to other services with their Facebook account.
Popular calorie-tracking app MyFitnessPal was among several apps discovered to be sharing user data with Facebook as soon as users open the application, likely without user permission
Other data that is sent to Facebook includes the user's unique ID with Google, which helps advertisers build a 'comprehensive profile' around a user, such as their gender, religion, interests, activities and other detailed information.
'For example, an individual who has installed the following apps that we have tested, Qibla Connect (a Muslim prayer app), Period Tracker Clue (a period tracker), Indeed (a job search app), My Talking Tom (a children’s app), could be potentially profiled as likely female, likely Muslim, likely jobseeker, likely parent,' the report stated.
Privacy International said some apps sent particularly sensitive and detailed data to Facebook, such as the travel booking app Kayak.
Kayak was found to be sharing detailed information about a person's flight searches with Facebook, like their departure city, airport and date, as well as their arrival city, airport and date, the number of tickets they purchased, whether the tickets purchased were for children and which class of tickets were purchased.
Since it reviewed Privacy International's report, Skyscanner said it has updated its