TikTok's sister app, Lemon8, is now one of the most popular on Apple's App Store

• Lemon8, TikTok's sister app, is surging in popularity ahead of a possible TikTok ban.
• Lemon8 uses TikTok's algorithm and is owned by the same Chinese company, ByteDance.
• The Supreme Court will decide this month on the fate of the law that could ban TikTok — and Lemon8.

TikTok owner ByteDance's other social media company, Lemon8, is growing in popularity amid confusion over a possible TikTok ban in the United States.

This week, Lemon8 shot to the No. 1 spot for free apps on Apple's App Store.

What users might not realize is that the law that would ban TikTok, if it is held up by the Supreme Court and then enforced by the administration of President-elect Donald Trump, would also likely ban Lemon8.

Lemon8 is the "sister app" to TikTok. It's a social media platform for photo slideshows, more similar to Pinterest or Instagram than TikTok, which is an exclusively short video platform. Lemon8 uses the same algorithm as TikTok. It is now the No. 2 free app, beating out competitors like ChatGPT.

But, like TikTok, its future is tenuous.

Congress passed the Protecting Americans from Foreign Adversary Controlled Applications Act in April. The law gives ByteDance, TikTok's Chinese parent company, until January 19 to sell TikTok. If a sale doesn't take place, TikTok will be banned in the United States.

TikTok filed a lawsuit in May, arguing that the law violates the First Amendment. The DC Circuit Court upheld the law on December 6. TikTok then filed an appeal to the Supreme Court on December 18. The court is expected to hear arguments on January 10.

Trump filed an amicus brief with the Supreme Court on December 27, asking the justices to pause the law until after his inauguration so he could "pursue a political resolution."

The law would also likely ban Lemon8. The bill's text specifically names TikTok and ByteDance as covered companies. However, its language is broad and could affect any company owned by a foreign "adversary" that permits users to "create an account or profile to generate, share, and view text, images, videos, real-time communications, or similar content."

Experts previously told Business Insider that Lemon8's success indicates that ByteDance is willing to introduce new apps to keep growing despite a TikTok ban.

"This is a huge business for ByteDance. They're not gonna go down without swinging," David Glancy, a professor at the Institute of World Politics, previously told BI.