Duolingo Shares rose nearly 7% on Thursday as a surge in users signed up to learn Mandarin and usage of Chinese social media apps soared red noteTikTok’s competitor.

The company confirmed to CNBC that 216% more Mandarin learners are using the app than a year ago. For context, Duolingo said Spanish is one of the most popular languages ​​on the app, growing 40% over the same period.

RedNote (known as Little Red Book in China) has quickly become the number one free app on the internet apple App Store, that’s where it stayed for most of the week. Rounding out the top five are TikTok’s Lemon8 app, American social media upstart Clapper, OpenAI’s ChatGPT and Yuan thread.

The Supreme People’s Court heard oral arguments in the case last week. The future of TikTok In the United States, a law can Effectively ban popular apps. The justices appeared to favor upholding the law, and a decision could come as soon as Friday. Douyin is It is said Preparing for a U.S. shutdown on Sunday.

RedNote has been the biggest beneficiary of U.S. user losses so far, with U.S. app downloads up 20 times from last week, according to data from market intelligence firm Sensor Tower. A Duolingo spokesperson told CNBC that the company’s marketing team is “forward-looking and already actively working on Red, managed by our team in China.”

Duolingo offers online and mobile courses in 42 languages. According to its websiteDuolingo has 48.8 million Spanish learners. French is the second most popular language on the app with 27.3 million users, while Chinese is eighth with 10.7 million users.

Duolingo shares rose 43% last year, outpacing the Nasdaq’s 29% gain.

watch: Artificial Intelligence will continue to be a catalyst for Duolingo