Chinese face-swapping app Zao rocketed to the top of Chinese app store charts within three days of release. The app allows users to drop a single image of their face, to replace people in popular movies, TV shows, and musical performances – all within seconds. The result is a downright very realistic deepfake video generated by machine learning.

See this video of a Chinese user replacing himself as Leonardo DiCaprio:

Or this of a user replacing himself as Sheldon Cooper from The Big Bang Theory:

Zao was developed by Momo, the maker of a popular Chinese dating app. Users were uploading their Zao deepfakes on WeChat and other social media platforms in China.

You just need one image, and why this matters: The app represents a radical advance in technology, as it can create convincing deepfake videos with just one image of the user, as opposed to the need to for hundreds of images for AI so that an app could create a convincing reproduction. As Gizmodo writes, users can provide multiple photos of themselves following on-screen prompts asking them to blink, open their mouths, and so on, to reproduce videos consisting of these actions – and the result is apparently neat.

Shady terms of use and ownership over user content: An earlier version of Zao’s user terms of use had “free, irrevocable, permanent, transferable, and relicense-able” to all user-generated content, per Bloomberg. In other words, the terms gave Zao full ownership and copyright over user-generated videos. Zao has now updated the terms, stating that it won’t use headshots or mini-videos uploaded by users for purposes other than to improve the app’s technology, or to purposes agreed to by the user.

Zao reportedly received a barrage of criticism from users over privacy, the app’s ratings went down and negative comments flooded the app reviews on the app store.

WeChat restricted access to Zao: WeChat blocked content shared from Zao, users can reportedly still upload Zao-created videos on WeChat but if they try to download the app or send an invite link to another user, WeChat shows a message stating that “this web page has been reported multiple times and contains security risks”, and access has been blocked.

What Zao is saying: A statement posted on Sept. 1 to Zao’s Weibo account says “we completely understand everybody’s concerns about the privacy issue. We are aware of the issue and we are thinking about how to fix the problems, we need a little time.” (accessed from TechCrunch)

Videos deleted from Zao are still available online: A twitter user said that after deleting the video he uploaded on Zao, it wasn’t available in the app’s ‘My Creations’ tab. However, the user said that Zao wasn’t entirely deleting the video since he could still access it on the internet. He also said that this goes against the app’s claims that it “will follow correct legal procedures to ensure the deletion of relevant data”.