android-reversing-expert

name	android-reversing-expert
description	Specialized workflow for reverse engineering Android applications (APKs/AABs). Use this when tasked with analyzing app logic, security auditing, identifying tracking/malware, or extracting assets/code from Android apps using tools like adb, apktool, and jadx.

Android Reversing Expert

Overview

This skill provides a systematic, expert-level workflow for reverse engineering Android apps. It focuses on identifying core logic, security vulnerabilities, and hidden behaviors, especially in QR code and utility applications.

Workflow Decision Tree

1. Static Analysis Phase (Start here)
   • Decompile APK using apktool for resources and jadx for Java/Kotlin code.
   • Analyze AndroidManifest.xml for permissions, activities, and intent filters.
   • Search for API keys, hardcoded URLs, and suspicious strings.
2. Dynamic Analysis Phase (Requires an active device/emulator)
   • Use adb to monitor logs, interact with activities, and inspect files.
   • Monitor network traffic (if proxy/interceptor is set up).
3. Deep Logic Inspection
   • Trace specific functions (e.g., QR scanning logic, data transmission).
   • Identify used libraries and their purposes.
4. Reporting
   • Synthesize findings into a structured expert report.

Static Analysis Guide

Decompilation

• Resources: apktool d <app.apk> -o <output_dir>
• Source Code: jadx -d <source_dir> <app.apk> (or use JADX-GUI for interactive search).

Key Files to Inspect

• AndroidManifest.xml: Look for android:debuggable="true", exported components, and sensitive permissions.
• assets/ and res/: Check for bundled configuration files, certificates, or hidden assets.
• smali/ (if Java source is unavailable or obfuscated): Expert analysis of low-level logic.

Dynamic Analysis with ADB

• Install: adb install <app.apk>
• Logcat: adb logcat | grep <package_name>
• Shell Access: adb shell
• Component Launching: adb shell am start -n <package>/<activity>
• File Inspection: adb shell ls -R /data/data/<package> (requires root for some paths).

Reporting Template

When finished, generate a report based on references/report_template.md.

Resources

• references/reversing_guide.md: Detailed step-by-step expert techniques.
• references/report_template.md: Structured format for professional reversing reports.
• scripts/check_app.sh: Helper script for quick ADB/AAPT analysis.