The hard drive on my laptop just crashed and I lost all the source code for an app that I have been working on for the past two months.
All I have is the APK file that is stored in my email from when I sent it to a friend.
Is there any way to extract my source code from this APK file?
Simplest way: use the online tool Decompiler, upload the apk and get the source code.
Procedure for decoding .apk files, step-by-step method:
Step 1:
Make a new folder and copy over the .apk file that you want to decode.
Now rename the extension of this .apk file to .zip (rename from filename.apk to filename.zip) and save it. Now you can access the classes.dex files. At this stage, you are able to see drawables, but not the .xml and .java files.
Step 2:
Now extract this .zip file in the same folder or a new folder.
Download dex2jar (Don't download the code, click on the releases button that's on the right, then download the file named dex2jar-X.X.zip) and extract it to the same folder or a new folder.
Move the classes.dex file into the dex2jar folder.
Now open Command Prompt and change the directory to that folder. Then write d2j-dex2jar classes.dex (for Mac or Ubuntu write ./d2j-dex2jar.sh classes.dex) and press enter. You now have the classes.dex.dex2jar file in the same folder.
Download java decompiler, Right click on jd-gui, click on Open File, and open classes.dex.dex2jar file from that folder: Now you get the class files.
Save all of these class files (In jd-gui, click File -> Save All Sources) by src name. At this stage, you get the Java code but the .xml files are still unreadable.
Step 3:
Now open another new folder
Put in the .apk file which you want to decode
Download the latest version of apktool AND apktool install window (both can be downloaded from the same link) and place them in the same folder
Open the Command Prompt
Now run command apktool if framework-res.apk (if you don't have it get it here)and next
apktool d myApp.apk (myApp.apk denotes the filename that you want to decode)
Now you get a file folder in that folder and can easily read the .xml files.
Step 4:
It's not any step, just copy the contents of both folders (both new folders) to the single one
AND ENJOY THE SOURCE CODE!
This is an alternative description - just in case someone got stuck with the description above. Follow the steps:
download apktool.bat (or apktool for Linux) and apktool_<version>.jar from http://ibotpeaches.github.io/Apktool/install/
rename the jar file from above to apktool.jar and put both files in the same folder
open a dos box (cmd.exe) and change into that folder; verify that a Java Environment is installed (for Linux check the notes regarding required libraries as well)
Start: apktool decode [apk file]
Intermediate result: resource files, AndroidManifest.xml
unzip APK file with an unpacker of your choice
Intermediate result: classes.dex
download and extract dex2jar-0.0.9.15.zip from http://code.google.com/p/dex2jar/downloads/detail?name=dex2jar-0.0.9.15.zip&can=2&q=
drag and drop classes.dex onto dex2jar.bat (or enter <path_to>\dex2jar.bat classes.dex in a DOS box; for Linux use dex2jar.sh)
Intermediate result: classes_dex2jar.jar
unpack classes_dex2jar.jar (might be optional depending on used decompiler)
decompile your class files (e.g. with JD-GUI or DJ Decompiler)
Result: source code
Note: it is not allowed to decompile third party packages; this guide is intended to recover personal source code from an APK file only; finally, the resulting code will most likely be obfuscated
While you may be able to decompile your APK file, you will likely hit one big issue:
it's not going to return the code you wrote. It is instead going to return whatever the compiler inlined, with variables given random names, as well as functions given random names. It could take significantly more time to try to decompile and restore it into the code you had, than it will be to start over.
Sadly, things like this have killed many projects.
For the future, I highly recommend learning a Version Control System, like CVS, SVN and git etc.
and how to back it up.
There is also a new application on the Play Store with which it is possible to decompile an apk (system applications too) and view the source code right on your smartphone. It saves the files to your SD card so you can view it on your computer too. It does not require root or something else.
Just install and have fun. I think this is the easiest way to decompile an app.
apktool is the best thing you can try. I have saved some xml with it, but honestly I don't know how it will work with the .java code.
I would recommend you to have a code repository even if your are the only coder. I've been using Project Locker for my own projects. It gives you free svn and git repos.
These two articles describe how to combine the use of apktool and dex2jar to take an APK file and create an Eclipse project that can build and run it.
http://blog.inyourbits.com/2012/11/extending-existing-android-applications.html
http://blog.inyourbits.com/2012/12/extending-existing-android-applications.html
Basically you:
Use apktool to get the resource files out of the apk
Use dex2jar to get a jar file that contains the classes in a format that Eclipse will like.
Create an Eclipse project point it at the resource files and the new jar file
Open the jar file with a zip utility and delete the existing resources
Open the jar file with JDGui to view the source code
Take whatever source code you need from JDGui, stick it in a class inside Eclipse and modify it
Delete that class from the jar file (so you don't have the same class defined multiple times)
Run it.
apktool will work. You don't even need to know the keystore to extract the source code (which is a bit scary). The main downside is that the source is presented in Smali format instead of Java. Other files such as the icon and main.xml come through perfectly fine though and it may be worth your time to at least recover those. Ultimately, you will most likely need to re-write your Java code from scratch.
You can find apktool here. Simply just download apktool and the appropriate helper (for Windows, Linux, or Mac OS). I recommend using a tool such as 7-zip to unpack them.
There are a few ways to do this:
Use the "Profile or Debug APK" feature in Android Studio 3.0.
It allows you to open and explore APKs in Android Studio. Classes are decompiled into smali. Resources are not extracted and things like "Go to Definition", "Find All References" and debugging don't work without the source code (android studio 3.0 canary 9). Some additional smali features might work with smalidea.
Use jadx.
Jadx decompiles the code in a given APK to java source files.
Use apktool.
Apktool is a command line tool which extracts resources and decompiles code into smali for a given apk. You can recompile using apktool also. Here's an example of it in action:
$ apktool d test.apk
I: Using Apktool 2.2.4 on test.apk
I: Loading resource table...
I: Decoding AndroidManifest.xml with resources...
I: Loading resource table from file: 1.apk
I: Regular manifest package...
I: Decoding file-resources...
I: Decoding values */* XMLs...
I: Baksmaling classes.dex...
I: Copying assets and libs...
I: Copying unknown files...
I: Copying original files...
$ apktool b test
I: Using Apktool 2.2.4 on test
I: Checking whether sources has changed...
I: Smaling smali folder into classes.dex...
I: Checking whether resources has changed...
I: Building resources...
I: Building apk file...
I: Copying unknown files/dir...
May be the easy one to see the source:
In Android studio 2.3, Build -> Analyze APK -> Select the apk that you want to decompile.
You will see it's source code.
Link for reference:
https://medium.com/google-developers/making-the-most-of-the-apk-analyzer-c066cb871ea2
This site https://www.apkdecompilers.com/ did it automatically.
I tried the site mentioned in the accepted answer first but that didn't work for me.
I personally recommend Show Java Android App to get the source code. You can download it from play store or from here
based on your condition, if your android apk:
Condition1: NOT harden (by Tencent Legu/Qihoo 360/...)
Choice1: using online service
such as:
using www.javadecompilers.com
goto:
http://www.javadecompilers.com/apk
Note: internally using Jadx
to auto decode from apk to java sourcecode
steps:
upload apk file + click Run + wait some time + click Download to get zip + unzip ->
sources/com/{yourCompanyName}/{yourProjectName}
is your expected java source code
Choice2: decompile/crack by yourself
use related tool to decompile/crack by yourself:
use jadx/jadx-gui convert apk to java sourcecode
download jadx-0.9.0.zip then unzip to got bin/jadx, then:
command line mode:
in terminal run: jadx-0.9.0/bin/jadx -o output_folder /path_to_your_apk/your_apk_file.apk
output_folder will show decoded sources and resources
sources/com/{yourCompanyName}/{yourProjectName} is your expected java sourcecode
GUI mode
double click to run jadx-0.9.0/bin/jadx-gui (Linux's jadx-gui.sh / Windows's jadx-gui.bat)
open apk file
it will auto decoding -> see your expected java sourcecode
save all or save as Gradle project
eg:
Condition2: harden (by Tencent Legu/Qihoo 360/...)
the main method of 3 steps:
apk/app to dex
dex to jar
jar to java src
detailed explanation:
Step1: apk/app to dex
use tool (FDex2/DumpDex) dump/hook out (one or multiple) dex file from running app
steps:
prepare environment
a rooted android
real phone
or emulator
here using Chinese Nox App Player夜神安卓模拟器
install your android apk
to the phone or emulator
installed Xposed Installer
install FDex2/DumpDex into XPosed and enable it
Note: need restart Xposed to make FDex2 work
FDex2 download address, Chinese:
脱壳工具 FDex2-CSDN下载
链接: https://pan.baidu.com/s/1lTF8CN96bxWpFwv7J174lg 提取码: 3e3t
install your android apk to phone/emulator
dump out dex from running app
run FDex2 then click your apk name to enable later to capture/hook out dex
(in phone/emulator) run your app
find and copy out the dump out whole apk resources in /data/data/com/yourCompanyName/yourProjectName
in its root folder normally will find several dex file
Step2: dex to jar
use tool (dex2jar) convert (the specific, containing app logic) dex file to jar file
download dex2jar got dex-tools-2.1-SNAPSHOT.zip, unzip got dex-tools-2.1-SNAPSHOT/d2j-dex2jar.sh, then
sh dex-tools-2.1-SNAPSHOT/d2j-dex2jar.sh -f your_dex_name.dex
eg:
dex-tools-2.1-SNAPSHOT/d2j-dex2jar.sh -f com.xxx.yyy8825612.dex
dex2jar com.xxx.yyy8825612.dex -> ./com.xxx.yyy8825612-dex2jar.jar
Step3: jar to java src
use one of tools:
Jadx
Procyon
GUI tool based on procyon:
Luyten
Bytecode Viewer
CRF
JD-GUI
some others:
Krakatau
Fernflower
Cavaj
convert jar to java src
for from jar to java src converting effect:
Jadx > Procyon > CRF >> JD-GUI
so recommend use: Jadx/jadx-gui
steps:
double click to run jadx-gui
open dex file
File -> save all
eg:
exported java src:
More detailed explanation can see my online ebook Chinese tutorial:
安卓应用的安全和破解
tutorial's source code on github: crifan/android_app_security_crack: 安卓应用的安全和破解
Below ONLINE tool:
http://www.javadecompilers.com/apk
it do ALL by one click: decompiled .java files + resources + xml (in one .zip file) with very good decompiler (jadx return java code in places/functions where other compiles return comments inside function like "unable to decompile" or some android assembler/machine code)
I'll show you other way to decompile the .apk files.
You can follow the first 2 steps from "prankul garg". So you have another opportunities:
Step 3':
Download the "JD-GUI", thats easy to found this one.
Open your .jar file in "jd-gui.exe". (File > Open file > 'found your .jar file'). After this procedure, you can save all resources in a .zip file.
So,
1st - You have to rename the .apk file to .zip
2nd - You have to decode .dex file (if you want, decode the .apk file to dex2jar, that's possible)
3rd - You have to decode .jar file with JD-GUI
Apktool for reverse engineering 3rd party, closed, binary Android apps.
It can decode resources to nearly original form and rebuild them after making some modifications.
It makes possible to debug smali code step by step. Also it makes working with an app easier because of project-like file structure and automation of some repetitive tasks like building apk, etc.
http://ibotpeaches.github.io/Apktool/
apktool is THE way to go.
Online apktool service exists as well: http://www.javadecompilers.com/apktool
Some limitations, obviously, exist due to the service ‘online nature’: you may extract and research assets and the manifest file, but it is impossible to recompile the application at the moment.
Still, this is a no-hassle way to 'open' the android application.
You can try DexPatcher. It even integrates with Android Studio. It uses Apktool and Dex2Jar internally.
You can use those tools independently as well.
Apktool decompiles apk, and extracts .dex files, which can further be converted to jar using Dex2Jar. Jar can be decompiled by using JD-GUI. You can see the Java code with the help of that tool. Although the similarity of decompiled code to the actual code cannot be guaranteed. There are some advanced code obfuscation tools available in the market, which mess up the code to make it difficult to decompile / understand. eg. Proguard
Android studio offers you to analyse any apk file.
1 - From build menu choose analyse apk option and select apk file.
2 - This will result in you the classes.dex file and other files.
3 - Click on classes.dex which will give you the list of folders, packages, libraries and files.
4 - From and android studio settings install a plugin called "Dex to Jar"
5 - click on any activity file of your extracted project and choose dex to jar from the build menu.
This will result in you the actual code of your java file.
Cheers.
Step 1:
Make a new folder and copy over the .apk file that you want to decode.
Now rename the extension of this .apk file to .zip (e.g. rename from filename.apk to filename.zip) and save it. Now you can access the classes.dex files, etc. At this stage you are able to see drawables but not xml and java files, so continue.
Step 2:
Now extract this .zip file in the same folder (or NEW FOLDER).
Download https://github.com/pxb1988/dex2jar/releases/tag/2.0 : dex2jar-2.0
Now open command prompt and change directory to that folder (or NEW FOLDER). Then execute :
d2j-dex2jar.bat classes.dex
Download this decompiler http://java-decompiler.github.io/ to decompile classes-dex2jar.jar
Step 3:
Now open another new folder
Put in the .apk file which you want to decode
Download the latest version of apktool AND apktool (https://ibotpeaches.github.io/Apktool/install/) install window (both can be downloaded from the same link) and place them in the same folder
Open a command window
Now run command like apktool if framework-res.apk (if you don't have it get it here)and next
apktool d myApp.apk (where myApp.apk denotes the filename that you want to decode)
now you get a file folder in that folder and can easily read the apk's xml files.
Copycontents of both folders to a single folder
Done !
In order to decompile APK and get the code from it you have multiple online tools & I usually prefer to use Online APK Decompiler.
It is very easy to use and within few minutes you will be able to download the source code from it.
If you want to download APK from playstore and decompile. you can easily download it from it too.
The simplest way is using Apk OneClick Decompiler. That is a tool package to decompile & disassemble APKs (android packages).
FEATURES
All features are integrated into the right-click menu of Windows.
Decompile APK classes to Java source codes.
Disassemble APK to smali code and decode its resources.
Install APK to phone by right-click.
Recompile APK after editing smali code and/or resources.
During recompile:
Optimize png images
Sign apks
Zipalign
REQUIREMENTS
Java Runtime Environment (JRE) must be installed.
You can download it from this link Apk OneClick Decompiler
Enjoy that.
I found the following as the simplest method:
Rename your app.apk to app.zip (Change extension from apk to zip)
Extract the zip file into a folder
Use JADX tool to read the source code, present in classes.dex file.
There's an app for that and generally takes just a few clicks and you are done.
https://github.com/Nuvolect/DeepDive-Android
Select Apps, under "Installed Apps" select your app. If it is not
there you can load the APK.
Select "Extract APK"
Select "Unpack APK"
Select "Decompile with Jadx". This can take a few seconds or a few minutes depending
on the speed of your device
After that you can browse the source code, download it to another computer with elFinder or search through it using Lucene.
In addition to Jadx it has CFR and Fernflower decompilers.
I developed a Tool - Code Analyzer, it runs in iPhone/iPad/Mac, to analyze Java/Android files, https://decompile.io
1. Extracting the source from a native Android application
The source code of a native Android application is not difficult to obtain, but it does require extra tools that are compatible with Windows, Mac, and Linux. My personal favorites when it comes to tools are dex2jar and JD-GUI.
If you’re unfamiliar with these tools, dex2jar will read Dalvik Executable files and convert them to the standard JAR format. JD-GUI will read JAR files and decompile the class files found in them.
To make the extraction process easier to understand, let’s start by creating a fresh native Android project:
android create project --target 19 --name TestProject --path . --activity TestProjectActivity --package com.nraboy.testproject
The above command will leave you with an Android project in your current command prompt path.
Since our project has an Activity class already included, lets jump straight into the build process. You can give me a hard time all day long about using Ant instead of Gradle or Maven, but for this tutorial I’m going to stick with it.
ant debug
The above command will create a debug build typically found at bin/TestProject-debug.apk.
Using your favorite unzip tool, extract the APK file. 7-zip is a popular tool, but if you’re on a Mac you can just run the following from the Terminal:
unzip TestProject-debug.apk
This will leave us with a bunch of files and folders, but one is important to us. Make note of classes.dex because it contains all of our source code. To convert it into something readable we need to run dex2jar on it. You can use dex2jar on Mac, Linux, and Windows, but I’m going to explain from a Mac perspective.
With the classes.dex file in your extracted dex2jar directory, run the following from the Terminal:
./dex2jar.sh classes.dex
Open the JD-GUI application that you downloaded because it is now time to decode the JAR and packaged class files. Open the freshly created classes_dex2jar.jar file and you should see something like the following:
See how easy it was to get to the source code of your native Android APK? Now what can you do to better protect yourself?
The Android SDK ships with Proguard, which is a obfuscation module. What is obfuscation you ask?
Obfuscation via Wikipedia:
Obfuscation (or beclouding) is the hiding of intended meaning in
communication, making communication confusing, willfully ambiguous,
and harder to interpret.
While obfuscation will not encrypt your source code, it will make it more difficult to make sense of. With Proguard configured, run Ant in release mode and your code should be obfuscated on build.
2. Extracting the source from a hybrid Android application
The source code of hybrid applications are by far the easiest to extract. You don’t need any extra software installed on your computer, just access to the APK file.
To make things easier to understand, lets first create a fresh Apache Cordova project and then extract it. Start by doing the following:
cordova create TestProject com.example.testproject TestProject
cd TestProject
cordova platform add android
During the project creation process you are left with the default Apache Cordova CSS, HTML, and JavaScript templates. That is fine for us in this example. Let’s go ahead and build our project into a distributed APK file:
cordova build android
You’re going to be left with platforms/android/ant-build/CordovaApp-debug.apk or something along the lines of platforms/android/ant-build/*-debug.apk.
Even though this is a debug build, it is still very usable. With 7-zip or similar installed, right click the APK file and choose to extract or unzip it. In the extracted directory, you should now have access to all your web based source files. I say web based because any Java files used by Apache Cordova will have been compiled into class files. However, CSS, HTML, and JavaScript files do not get touched.
You just saw how depressingly easy it is to get hybrid application source code. So what can you do to better protect yourself?
You can uglify your code, which is a form of obfuscation.
Doing this will not encrypt your code, but it will make it that much more difficult to make sense of.
If you want to uglify your code, I recommend you install UglifyJS since it is pretty much the standard as of now. If you prefer to use a task runner, Grunt and Gulp have modules for UglifyJS as well.
There are lots of applications and methods in the market to decompile the apk file into java class but if the app is compiled with ProGuard rule then you are in a big trouble because this rule will shrink all the dex files into a small character name and then you can not trace back the implementation. see https://developer.android.com/studio/build/shrink-code for mode clarification.
Happy Coding...
Single click solution (Windows only)
after reading this loooooonnnnnngggg post,
i have decided to create an automated process to decompile APKs in a single click,
i have decided to share it on github:
https://github.com/shaybc/apk-decompiler
simply unzip,
copy the apk you want to decompile into "apk-source" folder
and run "go.bat"
find the result in the: "apk-output" folder
thats it, enjoy
I've been driving myself crazy for days trying to get dex2jar to work on a fedora 31 laptop against an apk that just wasn't going to work. This python 3 script did the trick in minutes and installing jd-gui made class files human readable.
http://java-decompiler.github.io/
https://github.com/Storyyeller/enjarify
specifically, here's what I ran:
# i installed apktool before the rest of the stuff, may not need it but here it is
$> cd /opt
$> sudo mkdir apktool
$> cd apktool/
$> sudo wget https://raw.githubusercontent.com/iBotPeaches/Apktool/master/scripts/linux/apktool
$> sudo wget https://bitbucket.org/iBotPeaches/apktool/downloads/apktool_2.4.1.jar
$> sudo mv apktool_2.4.1.jar apktool.jar
$> sudo mv apktool* /usr/bin/
$> sudo chmod a+x /usr/bin/apktool*
# and enjarify
$> cd /opt
$> sudo git clone https://github.com/Storyyeller/enjarify.git
$> cd enjarify/
$> sudo ln -s /opt/enjarify/enjarify.sh /usr/bin/enjarify
# and finally jd-gui
$> cd /opt
$> sudo git clone https://github.com/java-decompiler/jd-gui.git
$> cd jd-gui/
$> sudo ./gradlew build
# I made an alias to kick of the jd-gui with short commandline rather than long java -jar blahblahblah :)
$> echo "jd-gui='java -jar /opt/jd-gui/build/launch4j/lib/jd-gui-1.6.6.jar'" >> ~/.bashrc
Now one should be able to rum the following to get class files:
$> enjarify yourapkfile.apk
And to start jd-gui:
$> jd-gui
Then just open your class files!
Use this tool
http://www.javadecompilers.com/
But recently, a new wave of decompilers has forayed onto the market: Procyon, CFR, JD, Fernflower, Krakatau, Candle.
Here's a list of decompilers presented on this site:
CFR -
Free, no source-code available, http://www.benf.org/other/cfr/
Author: Lee Benfield
Very well-updated decompiler! CFR is able to decompile modern Java features - Java 9 modules, Java 8 lambdas, Java 7 String switches etc.
It'll even make a decent go of turning class files from other JVM langauges back into java!
JD -
free for non-commercial use only, http://jd.benow.ca/
Author: Emmanuel Dupuy
Updated in 2015. Has its own visual interface and plugins to Eclipse and IntelliJ . Written in C++, so very fast. Supports Java 5.
Procyon -
open-source, https://bitbucket.org/mstrobel/procyon/wiki/Java%20Decompiler
Author: Mike Strobel
Fernflower -
open-source, https://github.com/fesh0r/fernflower
Author: Egor Ushakov
Updated in 2015. Very promising analytical Java decompiler, now becomes an integral part of IntelliJ 14. (https://github.com/JetBrains/intellij-community/tree/master/plugins/java-decompiler)
Supports Java up to version 6 (Annotations, generics, enums)
JAD -
given here only for historical reason. Free, no source-code available, jad download mirror
Author: Pavel Kouznetsov
Yes, it is possible.
There are tons of software available to reverse engineer an android .apk file.
Recently, I had compiled an ultimate list of 47 best APK decompilers on my website. I arranged them into 4 different sections.
Open Source APK Decompilers
Online APK Decompilers
APK Decompiler for Windows, Mac or Linux
APK Decompiler Apps
I hope this collection will be helpful to you.
Link: https://www.edopedia.com/blog/best-apk-decompilers/
https://code.google.com/p/javacv/#Quick_Start_for_OpenCV_and_FFmpeg
I am trying to configure openCV in Android.
The above link asked to download opencv-2.4.6.1-android-arm.jar, and ffmpeg-2.0.1-android-arm.jar
But I couldn;t find these jars anywhere,
Where can i download them.
The entire statement says-
Extract all the *.so files from javacv-android-arm.jar,
opencv-2.4.6.1-android-arm.jar, and ffmpeg-2.0.1-android-arm.jar
directly into the newly created "libs/armeabi" folder, without
creating any of the subdirectories found in the JAR files.
This is where you can find your jars. Download the javacv-bin package and see if your needed jars are present there.
Then if you have installed opencv properly in your system you need to add the required libraries to the project.
If you are using a windows system you can check this link.
If you are using ubuntu or linux systems then you need to add the path of the lib file to the Native Library location, which is normally inside the opencv/release/lib folder.
I have already told you where to get the libraries from. If you want to see the installation process for ubuntu, here is the link.
I hope this helps..For further queries please do comment, i will try and help to the best of my knowledge..cheers :)
Above reply to my query was perfect, Here I am just describing it more, if other needs help-
In Windows-7
Extract all the jar files and collect all the .so files. One ensurity
is there that no .so files will be repeated in any of the 3 jars, so
each jar has there own specific sets of .so fiies.
When you are copying the so to the emntioned named directory , please
take care the name , it is armeabi , a spelling mistake will ruin
your life.
Before class path setting , check your jre version, The Jre version
and OpenCV library version must match. Once you sure about jre
version , then add that in your class path , restart system and enjoy
I tried extracting apk file using apktool. I followed steps mentioned below.
Is there a way to get the source code from an APK file?
but i am not able to get it completely.I am not sure about where to put the apktool and how to decompile apk file.
i got following error while running apktool command
C:\Windows\System32>apktool.bat
Unable to access jarfile C:\Windows\System32\apktool.jar
Please help me to sort this out.
Thanks in advance
I faced the same problem. I my case i discovered that the jar file is present in a separate package and i had to download apktool1.5.2.tar.bz2 in addition to apktool-install-windows-r05-ibot.tar.bz2 .
Then i extracted the jar file and placed it in the same directory as apktool.
Hope it helps.
I also had this problem, then i noticed this in apktool.After done that,apktool gone well.
Rename downloaded jar to apktool.jar
I would create a folder called "apktool" somewhere where it won't be deleted ( a safe spot ).
Download the wrapper file & the apktool file itself via the Google code page (linked below). This is 2 files. One is a wrapper, OS specific, along with aapt ( which is needed for rebuild), and the other is simply apktool.jar which is the main application.
Once that is done, go into Environment Variables (PATH) for Windows, and add that current directory to it. So you can access apktool / aapt anywhere via command prompt.
http://code.google.com/p/android-apktool/
ApkTool + Dex2Jar + any java decompiler? Comon! This is old style :0)
Try NEW open-source APK and DEX decompiler called Jadx: https://sourceforge.net/projects/jadx/files/
It has also online version here: http://www.javadecompilers.com/apk/
I have followed https://ibotpeaches.github.io/Apktool/install/ link for windows and renamed jar file as "apktool.jar" with extra jar extension (ie.apktool.jar.jar) so I was getting "Error: Unable to access jarfile C:\APKtool\apktool.jar".
After renaming properly (removing extra .jar extension) , I am able to use "apktool.jar" properly.
I know it is silly mistake, but some time it happens :)
Those who are still facing same issue, follow below steps:
Download "https://raw.githubusercontent.com/iBotPeaches/Apktool/master/scripts/windows/apktool.bat"
download latest apktool from https://bitbucket.org/iBotPeaches/apktool/downloads/
Rename apktool_version.jar to apktool.jar
Put .bat and .jar in same folder.
Run apktool.bar d "path of apkfile/example.apk"