This article originally appeared on ABACUS The latest trend for China’s selfie-taking millennials? Nostalgia. While Star Wars fans in the West celebrated May 4th with Snapchat’s Chewbacca filter , Tencent’s selfie app Pitu gave China’s youth a taste of the past with a set of filters that turned new selfies into period portraits. The filters, called “Youth Portraits from My Past Life”, dressed users up in vintage Chinese fashion from the 1910s and 1920s -- when ladies donned the traditional cheongsam (known as qipao in Mandarin), and men wore either long Manchu robes or Western-style suits. The time-limited filters were released to mark the anniversary of the May Fourth Movement, which saw thousands of college students in Beijing rally on that date in 1919 to protest against the Treaty of Versailles. Many were outraged by the Allied Powers’ decision to transfer German territory in China to Japan. The filters were an instant hit. On Saturday, Pitu was the most downloaded free program on China’s App Store according to App Annie -- surpassing short video app Douyin and popular mobile game PlayerUnknown's Battlegrounds. Feeds on WeChat and the Twitter-like microblog Weibo were flooded with users posting their black-and-white selfies. Why one of China’s hottest apps is from the government But the filters’ sudden popularity prompted privacy concerns among some experts, who fear the app may be collecting personal information including users’ faces and locations. Pitu has denied it stores any selfies, and says it doesn’t record when and where a photo was taken. The “Past Life” filters are no longer available now. But a number of other time-travel filters still exist, including these ones that turn you into an ancient imperial concubine: For more insights into China tech, sign up for our tech newsletters , subscribe to our Inside China Tech podcast , and download the comprehensive 2019 China Internet Report . Also roam China Tech City , an award-winning interactive digital map at our sister site Abacus .