# Android Reverse Engineering Skill

## Installed Tools
- adb (Android Debug Bridge)
- fastboot
- apktool 2.11.1
- jadx 1.4.7 (CLI and GUI)
- apksigner
- zipalign

## Common Workflows

### APK Analysis
```bash
# Decompile APK
apktool d app.apk -o app_decompiled

# Recompile APK
apktool b app_decompiled -o app_modified.apk

# Sign APK
apksigner sign --ks keystore.jks app_modified.apk

# Analyze with JADX GUI
jadx-gui app.apk

# Analyze with JADX CLI
jadx -d output_dir app.apk
```

### ADB Commands
```bash
adb devices                        # List devices
adb shell                          # Open shell
adb install app.apk                # Install APK
adb uninstall com.package.name     # Uninstall
adb logcat                         # View logs
adb pull /sdcard/file.txt .        # Download file
adb push file.txt /sdcard/         # Upload file
adb shell pm list packages         # List installed packages
```

### APK Modification
```bash
# Full workflow
apktool d original.apk -o work_dir
# ... modify smali/resources ...
apktool b work_dir -o unsigned.apk
zipalign -v 4 unsigned.apk aligned.apk
apksigner sign --ks mykey.jks aligned.apk
```

## Tool Locations
- apktool: /opt/tools/apktool
- jadx: /opt/tools/jadx/bin/jadx
- jadx-gui: /opt/tools/jadx/bin/jadx-gui

## Security Notes
- Always verify APK signatures before installation
- Use isolated environment for unknown APKs
- Be careful with modified APKs - they can bypass security