How to Use the Command 'apktool' (with examples)

Apktool is a command-line tool used for reverse engineering Android APK files. It allows users to decode APK files to retrieve resources, decompile bytecode, and modify the APK for customization or analysis purposes. This article will illustrate three common use cases of the apktool command.

Use Case 1: Decode an APK file

Code:

apktool d path/to/file.apk

Motivation: Decoding an APK file is useful when you want to analyze or modify its contents. By using the apktool command with the d argument, you can extract the resources, assets, and manifest files from the APK package and obtain a readable form of the application.

Explanation:

• apktool: The command itself.
• d: The argument that tells apktool to decode the APK file.
• path/to/file.apk: The path to the APK file you want to decode.

Example Output:

Decoding file.apk
Decoding Successful. Output directory: path/to/output/directory

Use Case 2: Build an APK file from a directory

Code:

apktool b path/to/directory

Motivation: Building an APK file from a directory is helpful when you have modified the resources or source code of an application and want to generate a new APK package from these changes. This can be particularly useful when customizing an existing application or performing certain security analysis on the application.

Explanation:

• apktool: The command itself.
• b: The argument that tells apktool to build the APK file.
• path/to/directory: The path to the directory containing the decoded resources and modified files.

Example Output:

Building APK file...
Built path/to/output/directory/file.apk

Use Case 3: Install and store a framework

Code:

apktool if path/to/framework.apk

Motivation: Installing and storing a framework is necessary when modifying an APK that uses a custom framework. By using the apktool command with the if argument, you can install a framework APK and make it available for future use during the decoding or building process of APK files that depend on it.

Explanation:

• apktool: The command itself.
• if: The argument that tells apktool to install and store the framework.
• path/to/framework.apk: The path to the framework APK file you want to install.

Example Output:

Installing framework.apk
Framework installed successfully at path/to/framework.apk

Conclusion:

The apktool command is a powerful tool for reverse engineering Android APK files. It allows developers, security researchers, and enthusiasts to analyze, modify, and rebuild APKs by providing a straightforward command-line interface. Whether you want to decode an APK, build a modified APK, or install a custom framework, the apktool command has you covered.