We examine the impacts of mobile app category assortment of developers’ app portfolios on app performance in terms of quality and popularity. First, using data from the Apple App Store, we find a negative effect of portfolio diversity on developers’ app quality, which is negatively moderated by portfolio size. Second, we uncover spillover effects on app popularity, where existing (new) apps of a developer can influence the popularity of new (existing) apps both within and across app categories (only within the same app category). Importantly, our empirical analyses account for potential endogeneity biases using matching, selection, and simultaneous equations models.

我们从质量和流行度的角度研究了开发者应用组合的移动应用类别分类对应用性能的影响。首先，使用来自 Apple App Store 的数据，我们发现产品组合多样性对开发者的应用质量有负面影响，而这受到产品组合规模的负面影响。其次，我们发现了对应用流行度的溢出效应，开发者的现有（新）应用程序可以影响应用程序类别内和跨应用程序类别（仅在同一应用程序类别内）的新（现有）应用程序的流行度。重要的是，我们的实证分析使用匹配、选择和联立方程模型解释了潜在的内生性偏差。