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Understanding the Evolution of Mobile App Ecosystems: A Longitudinal Measurement Study of Google Play

The continuing expansion of mobile app ecosystems has attracted lots of efforts from the research community. However, although a large number of research studies have focused on analyzing the corpus of mobile apps and app markets, little is known at a comprehensive level on the evolution of mobile app ecosystems. Because the mobile app ecosystem is continuously evolving over time, understanding the dynamics of app ecosystems could provide unique insights that cannot be achieved through studying a single static snapshot. In this paper, we seek to shed light on the dynamics of mobile app ecosystems. Based on 5.3 million app records (with both app metadata and apks) collected from three snapshots of Google Play over more than three years, we conduct the first study on the evolution of app ecosystems from different aspects. Our results suggest that although the overall ecosystem shows promising progress in regard of app popularity, user ratings, permission usage and privacy policy declaration, there still exists a considerable number of unsolved issues including malicious apps, update issues, third-party tracking threats, improper app promotion behaviors, and spamming/malicious developers. Our study shows that understanding the evolution of mobile app ecosystems can help developers make better decision on developing and releasing apps, provide insights for app markets to identifying misbehaviors, and help mobile users to choose desired apps.