Apktool vs RetDec

Apktool is a command-line tool for reverse engineering Android APK files. It can disassemble an app’s resources into a form close to their original structure, then rebuild an app after changes such as translation or permission edits. Its analysis mode attempts to extract resources and the manifest for inspection without rebuilding. Apktool runs on Windows, Linux, and macOS; its official installation guide describes wrapper-script steps for those systems and requires Java 8 or later. Decode options include choosing resource-resolution behavior, skipping resources or source disassembly, and setting a framework directory. Build options include selecting an aapt2 binary, adding a generic Network Security Configuration file, and disabling APK repacking. The Apache license permits redistribution, modification, and integration into another project. Apktool is free, with no pricing tiers stated. Its FAQ says Android devices are not officially supported, and some OEM-modified “Magic APKs” may not decode or build. Builds are unsigned; copying a signature retains only the original APK signature v1 scheme.

RetDec is a free machine-code decompiler based on LLVM that reconstructs functions, types, and higher-level constructs as C or a Python-like language. It supports ELF, PE, Mach-O, COFF, AR archives, Intel HEX, and raw machine code, plus 32-bit Intel x86, ARM, MIPS, PIC32, and PowerPC, and 64-bit x86-64 and ARM64. Analysis includes static executable inspection, compiler and packer detection, and loading and instruction decoding. RetDec can use DWARF and PDB debugging information, reconstruct C++ class hierarchies from RTTI and vtables, and demangle GCC, MSVC, and Borland symbols. An integrated disassembler can generate call graphs, control-flow graphs, and statistics. It can be downloaded as a pre-built package, built from source, or run in Docker; related repositories provide IDA and Radare2 plugins. The project lists Windows 7 or later, Linux, and macOS, with experimental FreeBSD support. Installation requires about 5 to 6 GB of free disk space. The project says development is very limited, with issue responses potentially delayed up to one quarter.