A Chinese app named Zao that lets users superimpose their face on to celebrities has surged in popularity and is now the top free iPhone app in China.
But with its success comes new concerns about so-called deepfakes and how the company uses personal pictures uploaded by users.
The app was published by Momo, a Chinese social networking company that's traded on the Nasdaq. Shares were down fractionally Tuesday morning.
According to Reuters, Zao lets users upload a selfie and then place that picture on top of celebrities, such as Marilyn Monroe and Leonardo DiCaprio, making it appear as if they are the celebrity. The report said that users who upload pictures of themselves "agree to surrender the intellectual property rights to their face, and permit Zao to use their images for marketing purposes," Reuters said.
Here's an example from Twitter of someone posting their face on top of DiCaprio:
In another, a face is superimposed on Sheldon from TV show "The Big Bang Theory":
Deepfakes have surged in popularity recently and allow people, either through nefarious intent or just for fun, to make it appear as though someone real is doing or saying something they haven't done. In June, Facebook came under fire for not properly identifying a fake video that suggested that House Speaker Nancy Pelosi was stumbling through a speech when, in reality, she did not.
The fear is that if someone were to potentially upload a picture of a public figure, a celebrity or someone else, they could easily make it seem as though that person was doing something that never happened.
A similar app that surged in popularity in July also caused privacy firms. FaceApp let users upload pictures of themselves to see what they might look like when they're older, for example. After it went viral, users feared the Russian company could take advantage of the photos, since they were uploaded and stored on its personal servers.
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Correction: This article has been updated to reflect that Chinese social networking company Momo trades on the Nasdaq.