A mobile application named Ant Forest, designed to promote green behaviors and environmental conservation, has gained significant adoption in China. Despite its widespread use, limited research has been conducted on user stickiness. This study aimed to address this gap by collecting questionnaire responses from 318 participants and analyzing the data using a partial least squares estimation method. The findings highlighted that interpersonal and human-computer interactions had a positive impact on users’ perceived playfulness, leading to increased flow experience and satisfaction. Perceived playfulness, flow experience, and satisfaction emerged as key factors influencing user stickiness. Particularly, the relationship between perceived playfulness and user stickiness was mediated by flow experience and satisfaction. These results provide valuable insights into the role of gamification interactions in influencing user stickiness.