In mobile platform ecosystems, third-party developers create apps using platform-provided resources like software development kits (SDKs) and application programming interfaces (APIs). As app development becomes more complex and costly, many developers opt for multihoming by offering their apps across multiple platforms. This strategy expands the market reach but introduces new challenges in managing diverse platform resources. Cross-platform SDKs (CPSDKs) offer a solution by enabling development for multiple platforms using a single codebase. However, this approach presents a trade-off: while CPSDKs can simplify development, they may compromise platform-specific optimizations. We investigate this dilemma using a staggered difference-in-differences design on a comprehensive dataset of iOS and Android apps. Our study examines how multihoming and the choice of SDKs affect app quality. We find that multihoming generally improves app quality on the original launch platform. Interestingly, apps developed using CPSDKs lead to immediate quality improvements, while those using platform-native SDKs show delayed benefits. These findings contribute to understanding the intersection of technical design and platform strategy. For developers, it provides guidance on selecting SDKs that align with their strategic goals. For platform owners, it informs ecosystem governance strategies, highlighting the potential benefits of fostering multihoming to enhance overall app quality. By bridging theories from platform ecosystems and strategy, our study advances the understanding of complex dynamics in digital platform ecosystems through the lens of multihoming and SDK selections.
