Mobile Platform Development with Kotlin Multiplatform

Introduction

The book «Kotlin Multiplatform Mobile Development» (Pamela Hill, 2022, 282 pp.) is a practical guide to creating cross-platform mobile applications using Kotlin Multiplatform Mobile (KMM) technology. In an era when companies are looking to reduce development costs for iOS and Android, KMM offers an elegant solution: write business logic once in Kotlin, and UI natively for each platform. The author, Pamela Hill, a well-known Kotlin evangelist and developer, shares her experience and proven patterns.

What the book is about

The book covers the full cycle of creating a KMM project: from environment setup to publishing in app stores. The main focus is on modular architecture, organizing shared code (shared module), and integrating with platform APIs. Topics covered include:

• Setting up Gradle modules for KMM
• Creating shared code for network requests (Ktor), serialization (kotlinx.serialization), and data storage (SQLDelight)
• Using expect/actual for platform implementations
• Testing shared code and UI components
• Working with Compose Multiplatform to create a shared UI
• Integration with native frameworks (SwiftUI, Jetpack Compose)
• CI/CD and deployment

Who this book is for

The book is intended for developers already familiar with the Kotlin language and having basic experience in mobile development (Android or iOS). It will be difficult for beginners in mobile development — an understanding of the application lifecycle, working with Gradle, and architecture basics is assumed. However, for Android developers wanting to learn iOS, or iOS developers transitioning to Kotlin, this is an ideal start.

What the reader will learn

• How to set up a KMM project from scratch in Android Studio and Xcode
• How to organize a shared module and manage dependencies
• How to write platform-independent code for working with networks, databases, and the file system
• How to use expect/actual to call platform APIs (camera, geolocation, notifications)
• How to test shared code using JVM tests and platform tests
• How to create a shared UI with Compose Multiplatform and customize it for iOS and Android
• How to set up building and publishing the application for both platforms

Strengths

The main advantage of the book is its practical focus. Each chapter contains code examples that can be immediately applied in a real project. The author doesn't just list APIs, but explains why you should choose one approach or another. Particularly valuable are the sections on debugging and profiling KMM applications — topics rarely covered in documentation. The book is written in a lively style, with humor and real-world cases from the author's experience. The structure is logical: from simple to complex, with repetition of key concepts.

Who it is recommended for

The book will be useful for:

• Android developers looking to expand their skills to iOS
• iOS developers interested in Kotlin and cross-platform development
• Team leads and architects evaluating KMM for their projects
• Freelancers and small studios looking to reduce development time and budget

If you have already worked with KMM and are looking for advanced techniques — the book may seem basic to you. But for a first introduction to the technology, this is the best guide on the Russian and English markets.