Architecting iOS & Android SDKs for Third-Party Consumption

Building a mobile application is challenging, but building a mobile SDK meant to be consumed by other developers is an entirely different beast. When you ship an SDK (like a real-time video processing module), you are injecting your code into an unknown environment.

API Surface Design

The most critical aspect of an SDK is its public API. Once released, it is extremely difficult to introduce breaking changes without angering your integrators.

1. Keep it minimal: Expose only what is absolutely necessary. Hide implementation details behind strict access modifiers (internal in Swift, internal in Kotlin).
2. Configuration objects: Instead of passing ten arguments into an initialization function, use a strongly-typed Configuration object. It allows you to add non-breaking optional configurations later.

Binary Footprint & Dependencies

App developers guard their binary size fiercely. If your SDK adds 50MB to their app, they will drop it.

• Avoid heavy third-party dependencies: Do not include a massive library like Alamofire or Retrofit just to make a few network calls. Use URLSession on iOS and HttpURLConnection (or lightweight alternatives) on Android.
• Dynamic vs Static Linking: Understand how your XCFrameworks or AARs are linked and provide clear integration guides to avoid symbol collisions.

Building SDKs forces you to become a better citizen of the mobile ecosystem.