Everyone's seen them: FaceApp is the latest viral trend that has everyone doing a double-take over how they might look 50 years in the future -- but users might want to take a closer look at the privacy policy first.

The popular free mobile app that instantly alters the appearance of a persons face -- adding wrinkles, sun damage and grey hair -- has blown up on social media, shared by hundreds including a long list of celebrities.

FaceApp uses AI or artificial intelligence to "transform your face" aka-- the double take.

But while social media feeds fill up with the instantly aged pictures, new security concerns have risen for the recently top trending *More than 100,000 million people have downloaded the app from Google Play. And FaceApp is now the top-ranked app on the iOS App Store in 121 countries, according to App Annie) free mobile app -- especially in the wake of recent social media scandals, where other platforms have been taken to task for giving away users' private information.

And we thought we learned a lesson from Cambridge Analytica.

While according to FaceApp's terms of service people still own their own "user content" (read: face), the company owns a never-ending and irrevocable royalty-free license to do anything they want with it ... in front of whoever they wish:

You grant FaceApp a perpetual, irrevocable, nonexclusive, royalty-free, worldwide, fully-paid, transferable sub-licensable license to use, reproduce, modify, adapt, publish, translate, create derivative works from, distribute, publicly perform and display your User Content and any name, username or likeness provided in connection with your User Content in all media formats and channels now known or later developed, without compensation to you. When you post or otherwise share User Content on or through our Services, you understand that your User Content and any associated information (such as your [username], location or profile photo) will be visible to the public.

FaceApp terms of use

Whether that matters to you or not is your decision.

But what we have learned in the past few years about viral Facebook apps is that the data they collect is not always used for the purposes that we might assume. And, that the data collected is not always stored securely, safely, privately.

Once something is uploaded to the cloud, you've lost control whether or not you've given away legal license to your content. That's one reason why privacy-sensitive Apple is doing most of its AI work on-device.

And it's a good reason to be wary when any app wants access and a license to your digital content and/or identity.

FaceApp's privacy page also says they may share user content and your information with businesses. In case you didn't know.. FaceApp was developed by a small team from St. Petersburg, Russia and has not updated its privacy policy since 2017.

"Most images are deleted from our servers within 48 hours from the upload date," the company said in a lengthy statement provided to TechCrunch addressing the privacy concerns. (Representatives for FaceApp did not immediately respond to our request for comment.)

What remains concerning, however, is the language in the app's terms of service.