Version: v1.0.0-rc (Current)

🛒 kmp-iap

Version

This documentation is for kmp-iap v1.0.0-rc with simplified API design.

A comprehensive Kotlin Multiplatform library for in-app purchases on iOS and Android that conforms to the Open IAP specification.

🚀 What is kmp-iap?

This is an In App Purchase library for Kotlin Multiplatform. This project has been inspired by flutter_inapp_purchase and react-native-iap. We are trying to share same experience of in-app-purchase in Kotlin Multiplatform as in Flutter and React Native.

We will keep working on it as time goes by just like we did in flutter_inapp_purchase and react-native-iap.

✨ Key Features

Kotlin Multiplatform: Share IAP logic across iOS and Android
StoreKit 2 Support: Full StoreKit 2 support for iOS 15.0+ with automatic fallback
Billing Client v8: Latest Android Billing Client features
Type-safe: Complete type safety with Kotlin's strong typing
Coroutines Support: Modern async/await pattern with Kotlin Coroutines
StateFlow Integration: Reactive state management with StateFlow
Receipt Validation: Built-in receipt validation for both platforms

🎯 What this library does

Product Management: Fetch and manage consumable and non-consumable products
Purchase Flow: Handle complete purchase workflows with proper error handling
Subscription Support: Full subscription lifecycle management
Receipt Validation: Validate purchases on both platforms
Store Communication: Direct communication with App Store and Google Play
Error Recovery: Comprehensive error handling and recovery mechanisms

🛠️ Platform Support

Feature	iOS	Android
Products & Subscriptions	✅	✅
Purchase Flow	✅	✅
Receipt Validation	✅	✅
Subscription Management	✅	✅
Promotional Offers	✅	N/A
StoreKit 2	✅	N/A
Billing Client v8	N/A	✅

🔄 Version Information

Current Version: 1.0.0-rc
Kotlin Compatibility: Kotlin 2.1.10+
iOS Requirements: iOS 11.0+
Android Requirements: API level 24+

⚡ Quick Start

Get started with kmp-iap in minutes:

// In your build.gradle.kts
dependencies {
    implementation("io.github.hyochan:kmp-iap:1.0.0-rc.2")
}

Option 1: Using Global Instance (Simple)

import io.github.hyochan.kmpiap.kmpIapInstance
import io.github.hyochan.kmpiap.types.*

// Use the global singleton instance
kmpIapInstance.initConnection()

// Get products
val products = kmpIapInstance.requestProducts(
    ProductRequest(
        skus = listOf("product_id"),
        type = ProductType.INAPP
    )
)

// Request purchase
val purchase = kmpIapInstance.requestPurchase(
    UnifiedPurchaseRequest(
        sku = "product_id",
        quantity = 1
    )
)

// Finish transaction after validation
kmpIapInstance.finishTransaction(purchase, isConsumable = true)

Option 2: Create Your Own Instance (Recommended for Testing)

import io.github.hyochan.kmpiap.KmpIAP
import io.github.hyochan.kmpiap.types.*

// Create your own instance
val kmpIAP = KmpIAP()

// Initialize connection
kmpIAP.initConnection()

// Get products
val products = kmpIAP.requestProducts(
    ProductRequest(
        skus = listOf("product_id"),
        type = ProductType.INAPP
    )
)

// Request purchase
val purchase = kmpIAP.requestPurchase(
    UnifiedPurchaseRequest(
        sku = "product_id",
        quantity = 1
    )
)

// Finish transaction after validation
kmpIAP.finishTransaction(purchase, isConsumable = true)