With the rapid development of smart phone technology, people are becoming more and more addicted to mobile phones, which lead to depression and other undesirable social phenomena. The mobile app of Flower is such applications that can help people get rid of mobile phone addiction. The app's design is based on flow theory and tries to help people get rid of mobile addiction through sharing behavior. It uses the user's positive flow experience for app to replace the user's negative flow experience for mobile phone. Based on the technology acceptance theory, flow theory and extended-self theory, this paper explores the motivation and user’s acquisition of the sharing behavior in the use of the mobile app of Flower, and constructs a new model of internet sharing behavior. And the practical applications of app have proved that sharing behavior contributes to the solution of mobile phone addiction. We hope to be able to make a contribution to app designing and user behavior analysis.