China Business & EconomyChinese-Owned Stock Trading App Is Quietly Amassing US UsersSavePrintTraders wear masks as they work on the floor of the New York Stock Exchange on May 27, 2020. Lucas Jackson/File Photo/ReutersFan Yu12/13/2020|Updated: 12/21/2020News AnalysisThe U.S. stock market gyrations of 2020 need no introduction.We had a problem loading this article. Please enable javascript or use a different browser. If the issue persists, please visit our help center.