This post is part of a series on Kotlin Multiplatform: In subsequent blogs, I’ll dig into the trade-offs with representative code samples and my personal recommendations.

This post discusses what platform-dependent code is versus platform-independent code and overviews the three primary approaches for sharing code between iOS and Android applications using Kotlin Multiplatform, explicitly targeted at iOS engineers. With the Kotlin Multiplatform version of GapClick in production for over 18 months and having released another app utilizing KMM, I have valuable lessons to share for the technology I’ve chosen. As an iOS engineer with almost no Android experience, I investigated various ways to expand to Android. Given the complexities of writing multi-platform code, this post provides an overview, and future posts will dive deeper into these topics.Īfter I released Gap Click on iOS, Android users were not shy about sharing their feedback that they, too, were excited about it.Platform-independent code is written inside the KMM shared framework and can be used for any business logic for your application that does not directly depend upon any platform-specific code.

Platform-dependent code can be written entirely in Kotlin using KMM’s expect and actual syntax or by defining an interface in the KMM common module and implementing it natively in Android (using Kotiln) and iOS (using Swift).

One of the most essential skills for Kotlin Multiplatform Mobile cross-platform development is sensitivity to what code is platform-dependent or not.

Kotlin ios app