Relevant markets and market power of mobile apps

Antitrust investigations in the mobile app economy often require a definition of the relevant market of mobile apps and the evaluation of their market power. However, existing antitrust tools face significant challenges due to the non-price nature of mobile apps with multiple revenue sources, two competition margins at the mobile OS and mobile app levels, and the switching costs involved in the choice of mobile OSs. In this paper, we provide a description of the mobile app economy, including its essential components, players, and characteristics, and identify the challenges currently observed in antitrust investigations. We propose a model for mobile app users and advertisers that can address these issues and suggest a method for defining the relevant market of mobile apps and evaluating their market power, which is adaptable to markets with zero-priced products or multiple revenue sources beyond mobile apps.