The ZAO face swap app was launched last Friday and instantly became the most popular app in China. Due to potential privacy violation, the app is now being curbed on the Chinese social network WeChat reports Techcrunch.

The app uses so-called deep-frame technology, with which a person’s face can be placed over someone else’s face in a video. With ZAO, users can place themselves in a movie scene by uploading some selfies, preferably from different angles.

Via the social network WeChat, a sort of combination of Twitter, Facebook and WhatsApp, the app went viral when users massively shared their videos. Subsequently, the app was discredited due to a clause in the conditions.

The app’s terms and conditions stated that the user transferred all ownership rights over the videos to ZAO and allowed them to use them completely free, irrevocably and perpetually, as well as transferring the rights over the videos to others.

WeChat then decided to limit the use of the app, also because of the risks of the deepfake technology that can be used to spread fake news. Users can still upload previously made videos, but if they try to download the app or invite someone to Zao, they will be notified that the web page has been blocked for security reasons.

ZAO stated in a statement that they “understand everyone’s concerns about privacy terms” and that they are working on a solution. In the meantime, the terms state that the user data is only used to improve the app and that all files deleted by users are also deleted from the servers.