DexGuard

DexGuard is a commercial Android application protection tool developed by GuardSquare. It provides advanced obfuscation, hardening, and anti-tampering features designed to deter reverse engineering, tampering, and piracy of Android apps. DexGuard extends traditional obfuscation approaches and integrates into the Android build process to transform Dex bytecode and assets.

Key features include obfuscation of classes, methods, and fields; control-flow obfuscation to complicate decompiled output; string encryption; and resource obfuscation and protection. It also implements anti-tamper and integrity checks to detect modifications to the APK, along with anti-debugging and anti-emulation capabilities to impede dynamic analysis. DexGuard offers license protection to guard paid features and can harden reflective code and dynamic loading scenarios, reducing the risk of runtime discovery through common analysis techniques.

DexGuard is designed to work with Java and Kotlin Android apps and integrates with the Android Gradle Plugin. It is delivered as a Gradle-based plugin and is typically applied to release builds. Access to its full set of protections is available under a commercial license from GuardSquare, which may include support and guidance for integration and testing.

Limitations and considerations include that no protection is foolproof; determined attackers may still reverse engineer protected apps. DexGuard protections can increase APK size, affect build times, and occasionally require additional testing to ensure compatibility with third-party libraries and debugging workflows. It is commonly used in enterprise and demanding mobile security contexts where stronger defense against analysis and tampering is desired.