Shanghai girl Zhu Shuhan earned 18,000 yuan in three days and developed the virtual study companion app 在场. She is not the developer behind the widely circulated claims about million-yuan orders or the “frog foreign teacher”; that product was developed by 13-year-old girl Lv Sitong. Zhu’s mother, a Douyin主播, used livestreams and short videos to help sell the app, which explains why most of its orders came through online channels.