Add CONTRIBUTING and align README intro/footer

Add CONTRIBUTING.md tailored for Android module with quick start, dev setup, testing, code style, naming conventions, PR and commit guidelines, and maintainer release notes. Update README to OpenIAP Android intro linking to https://www.openiap.dev and add community footer.

Author: hyochan

CONTRIBUTING.md

@@ -0,0 +1,122 @@
+# Contributing to OpenIAP Android
+
+Thank you for your interest in contributing! We love your input and appreciate your efforts to make OpenIAP better.
+
+## Quick Start
+
+1. Fork the repository
+2. Create your feature branch (`git checkout -b feature/amazing-feature`)
+3. Make your changes
+4. Run tests (`./gradlew :openiap:test`)
+5. Commit your changes (`git commit -m 'Add amazing feature'`)
+6. Push to your branch (`git push origin feature/amazing-feature`)
+7. Open a Pull Request
+
+## Development Setup
+
+```bash
+# Clone your fork
+git clone https://github.com/YOUR_USERNAME/openiap-google.git
+cd openiap-google
+
+# Open in Android Studio (recommended)
+./scripts/open-android-studio.sh
+
+# Or build from CLI
+./gradlew :openiap:assemble
+
+# Run unit tests for the library module
+./gradlew :openiap:test
+
+# (Optional) Install and run the Example app
+./gradlew :Example:installDebug
+adb shell am start -n dev.hyo.martie/.MainActivity
+```
+
+## Code Style
+
+- Follow the official Kotlin Coding Conventions
+- Use meaningful, descriptive names for types, functions, and variables
+- Keep functions small and focused
+- Add comments when they clarify intent (avoid redundant comments)
+
+### Naming Conventions
+
+- **OpenIap prefix for public models (Android)**
+  - Prefix all public model types with `OpenIap`.
+  - Examples: `OpenIapProduct`, `OpenIapPurchase`, `OpenIapActiveSubscription`, `OpenIapRequestPurchaseProps`, `OpenIapProductRequest`, `OpenIapReceiptValidationProps`, `OpenIapReceiptValidationResult`.
+- Private/internal helper types do not need the prefix.
+- When renaming existing types, provide a public typealias from the old name to the new name to preserve source compatibility and migrate usages incrementally when feasible.
+
+## Testing
+
+All new features must include unit tests (JUnit + coroutines test):
+
+```kotlin
+@Test
+fun yourFeature_isCorrect() = kotlinx.coroutines.test.runTest {
+    // Arrange
+    // val module = FakeOpenIapModule()
+
+    // Act
+    // val result = store.yourMethod()
+
+    // Assert
+    // assertEquals(expected, result)
+}
+```
+
+Run tests locally with:
+
+```bash
+./gradlew :openiap:test
+```
+
+## Pull Request Guidelines
+
+### ✅ Do
+
+- Write clear PR titles and descriptions
+- Include tests for new features
+- Update documentation when needed
+- Keep changes focused and small
+
+### ❌ Don't
+
+- Mix unrelated changes in one PR
+- Break existing tests
+- Change code style without discussion
+- Include commented-out or dead code
+
+## Commit Messages
+
+Keep them clear and concise:
+
+- `Add purchase error recovery`
+- `Fix subscription status check`
+- `Update Google Play Billing integration`
+- `Refactor transaction handling`
+
+## Release Process (Maintainers Only)
+
+When a PR is merged, maintainers handle releases using semantic versioning (major.minor.patch):
+
+1. Bump version (e.g., `OPENIAP_VERSION` in `gradle.properties` or release property)
+2. Update changelog (if applicable)
+3. Tag and create a GitHub Release
+4. Publish to Maven Central via CI (or `./gradlew publish` if configured)
+
+Availability: artifacts appear on Maven Central shortly after the release propagates.
+
+## Questions?
+
+Feel free to:
+
+- Open an issue for bugs or features
+- Start a discussion for questions
+- Tag @hyodotdev for urgent matters
+
+## License
+
+By contributing, you agree that your contributions will be licensed under the MIT License.
+

README.md

@@ -1,11 +1,25 @@
-# OpenIAP GMS
+# OpenIAP Android
+
+<div align="center">
+  <img src="https://openiap.dev/logo.png" alt="OpenIAP Logo" width="120" height="120">
+  
+  <p><strong>Android implementation of the <a href="https://www.openiap.dev/">OpenIAP</a> specification using Google Play Billing.</strong></p>
+</div>
+
+<br />
 
 [![Maven Central](https://img.shields.io/maven-central/v/dev.hyo.openiap/openiap-google)](https://central.sonatype.com/artifact/dev.hyo.openiap/openiap-google)
 [![API](https://img.shields.io/badge/API-21%2B-brightgreen.svg?style=flat)](https://android-arsenal.com/api?level=21)
 [![License](https://img.shields.io/badge/License-MIT-blue.svg)](https://opensource.org/licenses/MIT)
 
+OpenIAP Android module: https://www.openiap.dev/
+
 Modern Android Kotlin library for in-app purchases using Google Play Billing Library v8.
 
+## 🌐 Learn More
+
+Visit [**openiap.dev**](https://openiap.dev) for complete documentation, guides, and the full OpenIAP specification.
+
 ## 🎯 Overview
 
 OpenIAP GMS is a modern, type-safe Kotlin library that simplifies Google Play in-app billing integration. It provides a clean, coroutine-based API that handles all the complexity of Google Play Billing while offering robust error handling and real-time purchase tracking.
@@ -16,7 +30,7 @@ OpenIAP GMS is a modern, type-safe Kotlin library that simplifies Google Play in
 - ⚡ **Kotlin Coroutines** - Modern async/await API
 - 🎯 **Type Safe** - Full Kotlin type safety with sealed classes
 - 🔄 **Real-time Events** - Purchase update and error listeners
-- 🧵 **Thread Safe** - Concurrent operations with proper synchronization  
+- 🧵 **Thread Safe** - Concurrent operations with proper synchronization
 - 📱 **Easy Integration** - Simple singleton pattern with context management
 - 🛡️ **Robust Error Handling** - Comprehensive error types with detailed messages
 - 🚀 **Production Ready** - Used in production apps
@@ -67,18 +81,18 @@ class MainActivity : AppCompatActivity() {
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
-        
+
         openIAP = OpenIAP.getInstance()
-        
+
         // Set up listeners
         openIAP.addPurchaseUpdateListener { purchase ->
             handlePurchaseUpdate(purchase)
         }
-        
+
         openIAP.addPurchaseErrorListener { error ->
             handlePurchaseError(error)
         }
-        
+
         // Initialize connection
         lifecycleScope.launch {
             try {
@@ -175,9 +189,7 @@ suspend fun requestPurchase(
 )
 
 suspend fun requestPurchase(params: Map<String, Any?>, activity: Activity)
-
 suspend fun finishTransaction(purchase: OpenIapPurchase, isConsumable: Boolean? = null)
-
 suspend fun getAvailablePurchases(): List<OpenIapPurchase>
 suspend fun getAvailablePurchases(options: Map<String, Any?>?): List<OpenIapPurchase> // options ignored on Android
 suspend fun getAvailableItemsByType(type: String): List<OpenIapPurchase>
@@ -273,7 +285,7 @@ sealed class OpenIapError : Exception {
 
 ## 🔄 Purchase Flow
 
-1. **Initialize**: Call `initConnection()` 
+1. **Initialize**: Call `initConnection()`
 2. **Fetch Products**: Use `fetchProducts()` to load available items
 3. **Request Purchase**: Call `requestPurchase()` with the product SKU
 4. **Handle Events**: Listen for purchase updates via listeners
@@ -301,15 +313,17 @@ cd openiap-google
 ### Test Products
 
 For development, use Google Play's test SKUs:
+
 - `android.test.purchased` - Always succeeds
-- `android.test.canceled` - Always cancels  
+- `android.test.canceled` - Always cancels
 - `android.test.item_unavailable` - Always fails
 
 For production testing, configure products in Google Play Console and use internal testing.
 
 ## 📱 Sample App
 
 The included sample app demonstrates:
+
 - ✅ Connection management with retry logic
 - ✅ Product listing and purchase flow
 - ✅ Real-time purchase event handling
@@ -374,11 +388,13 @@ openIAP.requestPurchase(
 ### Common Issues
 
 1. **Product not found**
+
    - Ensure products are configured in Google Play Console
    - App must be uploaded to Google Play Console (even as draft)
    - Wait up to 24 hours for products to become available
 
 2. **Billing unavailable**
+
    - Verify Google Play Services are installed and updated
    - Check that app is signed with release key for testing
    - Ensure billing permissions are in AndroidManifest.xml
@@ -404,7 +420,7 @@ if (BuildConfig.DEBUG) {
 ```
 MIT License
 
-Copyright (c) 2024 hyodo.dev
+Copyright (c) 2024 hyo.dev
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
@@ -432,9 +448,11 @@ Contributions are welcome! Please read our contributing guidelines and submit pu
 ## 📞 Support
 
 - **Issues**: [GitHub Issues](https://github.com/hyodotdev/openiap-google/issues)
-- **Documentation**: [Wiki](https://github.com/hyodotdev/openiap-google/wiki)  
-- **Discussions**: [GitHub Discussions](https://github.com/hyodotdev/openiap-google/discussions)
+- **Discussions**: [GitHub Discussions](https://github.com/hyodotdev/openiap.dev/discussions)
 
 ---
 
-Made with ❤️ by [hyodo.dev](https://hyodo.dev)
+<div align="center">
+  <strong>Built with ❤️ for the OpenIAP community</strong>
+  
+</div>