An analysis of the mobile app review landscape: trends and implications

Apple Inc.'s App Store offers a distribution mechanism for apps and a public review system which allows users to express opinions regarding purchased apps. The ratings and reviews left by users have the potential to influence new users and, hence, have an impact on the commercial feasibility of an app. Current literature has extensively investigated reviews of books, movies and hotels. However, there is a limited understanding of reviews for mobile apps. In this work, we analyse a large sample of reviews for top rated apps in order to determine the nature of the reviews, and how these reviews evolve over time. We performed a statistical analysis of approximately 8 million app reviews to identify the general distribution of review size, the rate of growth for reviews, and analyse the change of both rating and review size over time using the Gini coefficient. We found that (i) most reviews are short and the majority of apps receive well under 50 reviews in their first year, (ii) apps receive a higher number of short reviews in comparison to long reviews as they age, (iii) around half of the apps decrease in user perceived quality over time, as reflected by the star ratings, and (iv) the rate of review growth and profile of reviews changes significantly between various apps as well as categories. Developers can use the data presented in this work to benchmark their app. Our approach offers insights for both newer and older apps as we analyse reviews over time. We recommend that developers regularly monitor early reviews and continuously refine their app in order to ensure they meet changing user expectations.