Some popular smartphone apps are sending users’ data to Facebook, even when app users don’t have a Facebook account.
Apps on Android smartphones, including music streaming service Spotify and travel site TripAdvisor, were among apps found to be sending data by researchers at campaign group Privacy International.
The researchers found many of the apps tested were automatically sending data to Facebook as soon as the apps were opened.
For the majority of the apps tested, Facebook was notified when a person began using the app.
Also conveyed was information about the type of smartphone being used, and the user’s suspected location based on time zone and language data.
In addition, they found that in some cases (not involving Spotify or TripAdvisor) a person’s unique Google advertising identifier was being included in the data sent.
That could allow Facebook to build up a detailed picture of the person in question, depending on the number of times it was sent the Google identifier by different apps. For example, if the unique identifier was sent by a job searching app and by a Muslim prayer app, the person might be identifiable as a Muslim job seeker.
“Without any further transparency from Facebook, it is impossible to know for certain, how the data that we have described in this report is being used,” the Privacy International campaigners said.
The report included responses from a number of the companies whose apps were tested. The tested apps were for Android phones only, not iPhones.
Spotify said it was “committed to transparency and fairness” and evaluating the report’s findings.
TripAdvisor said it was committed to engaging with Privacy International and that “respecting the data protection rights of our users is of utmost importance”.
Google said it had controls in place to allow people to change their advertising identifier.
Facebook said: “it’s important for people to have access when we receive information about them when they’re not using our services, and to have control over whether we associate this information with them.
“Recognizing the value of improvements in this area, we’re currently working on a suite of changes.”