Standardize or let a thousand flowers bloom? interface design coordination between software platforms and

Software platform ecosystems are emerging as a dominant model for IT-based services. To accelerate third-party development, platform owners often waive restrictions on app user interfaces to provide app developers with more autonomy in interface design. The literature has indicated, however, that standardized interface design across products is a strategic necessity for firms to introduce and manage their product lines, suggesting that platform owners should not waive restrictions on app user interfaces. This tension between the two approaches raises a crucial research question: Does standardized interface design used by apps and their host platform benefit the platform and apps that it hosts? Specifically, does the coordinated design approach enhance or hinder usage between the platform and apps such that apps attract usage from their host platform and vice versa? Drawing on the theory of basic Gestalts, we theorize the three interface design properties of interface similarity, embeddedness, and synchrony, and extend the theory to investigate how these properties help both apps and their host platform attract each other's users, thus reflecting derivative usage between them. We performed a randomized field experiment to test the proposed hypotheses. The results reveal that interface similarity, embeddedness, and synchrony of the app-platform interface design strengthen users' grouping perception of the platform and its apps, thus enhancing platform-to-app forward derivative usage. Contrary to our expectations, we found that this strengthened grouping perception does not improve the app-to-platform backward derivative usage. These findings have crucial implications for the value of interface design in software platform ecosystems.