This document discusses a study that analyzed how the average user ratings of Android apps correlate with the fault- and change-proneness of the APIs used by the apps. The study found that apps with high user ratings tend to use APIs that are less fault- and change-prone than those used by low-rated apps. The document also notes that existing mobile app research did not examine this relationship between API issues and user ratings. It proposes further investigating this relationship to provide empirical evidence and insights into what impacts the success of apps.