Categories: Mobility

3 Simple Steps to Decompile Android Mobile Apps (APK)

The article represents 3 simple steps to decompile an Android mobile app.

Following are different tools that will be needed to decompile the android downloadable apk file to Java files:

Dex2Jar: The tools reads .dex files and convert the same to smali files.
JD-GUI: A standalone graphical utility that displays Java source codes of *.class files

Following are set of things I did to decompile android mobile application (apk files).

Download the android version of mobile application. The android version comes with apk extension.
Execute following command with dex2jar application to extract mobile apps files with apk extension in form of *smali files: d2j-dex2jar.bat <appname>.apk
Execute following command with JD-GUI application: jd-gui.exe <appname>-dex2jar.jar

From executing JD-GUI command, what you get is Java source code file which could be viewed and studied. Following is the screenshot of JD-GUI tool displaying WhatsApp code.

fig: JD-GUI Displaying WhatsApp Code

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Ajitesh Kumar

I have been recently working in the area of Data analytics including Data Science and Machine Learning / Deep Learning. I am also passionate about different technologies including programming languages such as Java/JEE, Javascript, Python, R, Julia, etc, and technologies such as Blockchain, mobile computing, cloud-native technologies, application security, cloud computing platforms, big data, etc. I would love to connect with you on Linkedin.
Check out my latest book titled as First Principles Thinking: Building winning products using first principles thinking.

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Ajitesh Kumar

I have been recently working in the area of Data analytics including Data Science and Machine Learning / Deep Learning. I am also passionate about different technologies including programming languages such as Java/JEE, Javascript, Python, R, Julia, etc, and technologies such as Blockchain, mobile computing, cloud-native technologies, application security, cloud computing platforms, big data, etc. I would love to connect with you on Linkedin. Check out my latest book titled as First Principles Thinking: Building winning products using first principles thinking.