SplitKiller

Merge split APKs (XAPK/APKM) into single installable APKs with proper v1+v2+v3 signatures

📱 Features

• APK Merging: Merge XAPK/APKM/ZIP files containing split APKs into a single installable APK
• Proper Signing: Sign merged APKs with v1 (JAR) + v2 + v3 signature schemes for maximum compatibility
• App Extraction: Extract installed apps (including split APKs) and create XAPK files
• Custom Keys: Generate and manage custom RSA 2048-bit signing keys with BKS keystores
• File Browser: Built-in file picker with modern Material You design
• Real-time Logs: Live console logs for merge and extraction operations
• Material You: Beautiful UI with dynamic theming and amber/gunmetal color scheme
• Batch Operations: Extract multiple apps at once

🎯 Why SplitKiller?

Modern Android apps often come as split APKs (XAPK, APKM) which cannot be installed directly. SplitKiller merges these splits into a single APK that:

• ✅ Installs on any Android device (7.0+)
• ✅ Preserves all resources, libraries, and assets
• ✅ Properly signed with industry-standard tools
• ✅ Works with large APKs (800MB+) without memory issues

🛠️ Tech Stack

• Language: Kotlin
• UI: Jetpack Compose with Material 3
• Architecture: MVVM (Model-View-ViewModel)
• Navigation: Navigation Compose
• Storage: DataStore for preferences
• Signing: Google's official apksig library (v8.7.2)
• APK Manipulation: APKEditor library
• Cryptography: BouncyCastle (bcprov, bcpkix)

📋 Requirements

• Min SDK: 24 (Android 7.0 Nougat)
• Target SDK: 35 (Android 15)
• Compile SDK: 36
• Permissions:
  • READ_EXTERNAL_STORAGE / READ_MEDIA_IMAGES (Android 13+)
  • WRITE_EXTERNAL_STORAGE (Android 12 and below)
  • MANAGE_EXTERNAL_STORAGE (Android 11+)
  • REQUEST_INSTALL_PACKAGES
  • QUERY_ALL_PACKAGES

🚀 Getting Started

Installation

1. Clone the repository:

git clone https://github.com/THToufique/SplitKiller.git
cd SplitKiller

2. Open in Android Studio (Ladybug or later)

3. Build and run on your device

Usage

Merging Split APKs

1. Navigate to Merge screen
2. Tap Select File to choose an XAPK/APKM/ZIP file
3. Select signature scheme (default: v1+v2+v3)
4. Choose signing key (default: testkey)
5. Tap Merge APK
6. Find merged APK in /storage/emulated/0/SplitKiller/

Extracting Installed Apps

1. Navigate to Extract screen
2. Browse installed apps (use search to filter)
3. Select apps to extract
4. Tap Extract Selected
5. Find XAPK files in /storage/emulated/0/SplitKiller/

Managing Signing Keys

1. Navigate to Key Manager screen
2. Tap Create New Key
3. Enter key details (alias, password, organization)
4. Generated keys are stored in app's private directory
5. Use custom keys when merging APKs

📁 Project Structure

app/src/main/java/com/ripp3r/splitkiller/
├── data/
│   ├── ApkMerger.kt          # Core APK merging logic
│   ├── KeystoreManager.kt    # APK signing with apksig
│   ├── AppExtractor.kt       # Extract installed apps
│   └── SettingsManager.kt    # DataStore preferences
├── model/
│   ├── AppInfo.kt            # App information data class
│   ├── SignatureScheme.kt    # Signature scheme enum
│   └── SigningKey.kt         # Signing key data class
├── ui/
│   ├── Navigation.kt         # Navigation setup
│   ├── screens/
│   │   ├── MainScreen.kt     # Dashboard + extraction logs
│   │   ├── MergeScreen.kt    # File selection + merge logs
│   │   ├── ExtractScreen.kt  # App list with search
│   │   ├── FileBrowserSheet.kt # Custom file picker
│   │   ├── KeyManagerScreen.kt # Key management
│   │   └── SettingsScreen.kt # App settings
│   └── theme/
│       ├── Color.kt          # Material You colors
│       ├── Theme.kt          # Theme configuration
│       └── Type.kt           # Typography
├── viewmodel/
│   ├── MergeViewModel.kt     # Merge operations
│   ├── ExtractViewModel.kt   # Extract operations
│   ├── KeyManagerViewModel.kt # Key management
│   └── SettingsViewModel.kt  # Settings
├── util/
│   └── AppLogger.kt          # Logging system
└── MainActivity.kt           # Entry point

🔑 Key Technical Decisions

Why Google's apksig?

Initially, we implemented custom v2/v3 signing, but it caused OutOfMemoryError on large APKs (800MB+). Google's official apksig library:

• ✅ Memory-efficient streaming
• ✅ Proper v1+v2+v3 implementation
• ✅ Same library used by Android Studio
• ✅ Battle-tested and maintained

Why APKEditor?

APKEditor provides:

• Proper resource table merging using ApkBundle.loadApkDirectory()
• Manifest manipulation
• Efficient handling of large APK files
• No memory issues with 800MB+ APKs

Output Directory

All merged APKs and extracted XAPKs are saved to:

/storage/emulated/0/SplitKiller/

🎨 UI/UX Highlights

• Material You Design: Dynamic theming with system colors
• Bottom Sheets: Modern popup sheets for file selection and options
• Real-time Logs: Color-coded console logs with Material Icons
• Dark/Light Themes: Supports system, light, and dark themes
• Responsive: Adapts to different screen sizes

🐛 Known Issues & Solutions

Issue: "Not signed" after merging

Solution: We use Google's apksig library which properly signs APKs with v1+v2+v3 schemes.

Issue: OutOfMemoryError on large APKs

Solution: apksig handles memory efficiently with streaming.

Issue: Icons missing after merge

Solution: We use ApkBundle.loadApkDirectory() for proper resource table merging.

🤝 Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

🙏 Acknowledgments

• Google's apksig - Official APK signing library
• APKEditor - APK manipulation library
• BouncyCastle - Cryptography library
• Material Design 3 - UI design system

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Made with ❤️ using Kotlin and Jetpack Compose

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