The influence of App churn on App success and StackOverflow discussions

Gauging the success of software systems has been difficult in the past as there was no uniform measure. With mobile Application (App) Stores, users rate each App according to a common rating scheme. In this paper, we study the impact of App churn on the App success through the analysis of 154 free Android Apps that have a total of 1.2k releases. We provide a novel technique to extract Android API elements used by Apps that developers change between releases. We find that high App churn leads to lower user ratings. For example, we find that on average, per release, poorly rated Apps change 140 methods compared to the 82 methods changed by positively rated Apps. Our findings suggest that developers should not release new features at the expense of churn and user ratings. We also investigate the link between how frequently API classes and methods are changed by App developers relative to the amount of discussion of these code elements on StackOverflow. Our findings indicate that classes and methods that are changed frequently by App developers are in more posts on StackOverflow. We add to the growing consensus that StackOverflow keeps up with the documentation needs of practitioners.