自从这些答案被发布以来，很多事情都发生了变化。现在有很多简单的GUI工具，比如:

APK Easy Tool for Windows (GUI tool, friendly)
Bytecode Viewer - APK/Java Reverse Engineering Suite
URET Android Reverser Toolkit

找到他们最好的地方是在XDA开发者论坛上。

最近Debian有Python包androguard:

Description-en: full Python tool to play with Android files
 Androguard is a full Python tool to play with Android files.
  * DEX, ODEX
  * APK
  * Android's binary xml
  * Android resources
  * Disassemble DEX/ODEX bytecodes
  * Decompiler for DEX/ODEX files

安装相应的软件包:

sudo apt-get install androguard python-networkx

反编译DEX文件:

$ androdd -i classes.dex -o ./dir-for-output

从Apk +反编译中提取classes.dex:

$ androdd -i app.apk -o ./dir-for-output

Apk文件就是Java的JAR文件，你可以通过以下方法从JAR文件中提取文件:

$ unzip app.apk -d ./dir-for-output

下载APK文件后，您需要执行以下步骤以获得可编辑的java代码/文档。

Convert your apk file to zip (while start your download don't go with "save" option , just go with "save as" and mention your extension as .zip) by doing like this you may avoid APKTOOL... Extract the zip file , there you can find somefilename.dex. so now we need to convert dex -> .class To do that, you need "dex2jar"(you can download it from http://code.google.com/p/dex2jar/ , after extracted, in command prompt you have to mention like, [D:\dex2jar-0.09>dex2jar somefilename.dex] (Keep in mind that your somefilename.dex must be inside the same folder where you have keep your dex2jar.) Download jad from http://www.viralpatel.net/blogs/download/jad/jad.zip and extract it. Once extracted you can see two files like "jad.exe" and "Readme.txt" (sometimes "jad.txt" may there instead of "jad.exe", so just rename its extension as.exe to run) Finally, in command prompt you have to mention like [D:\jad>jad -sjava yourfilename.class] it will parse your class file into editable java document.

在使用dex2jar/apktool时，有时会出现坏代码，最明显的是在循环中。为了避免这种情况，可以使用jadx，它可以将dalvik字节码反编译成java源代码，而不需要像dex2jar那样先创建.jar/.class文件(我认为apktool使用dex2jar)。它也是开源的，正在积极开发中。它甚至有一个GUI，专为GUI爱好者设计。试一试!

很容易

获取这些工具:

Dex2jar将dex文件转换为jar文件 以查看jar中的Java文件

源代码可读性很强，因为dex2jar做了一些优化。

过程:

下面是如何反编译的过程:

步骤1:

将test_apk-debug.apk中的classes.dex转换为test_apk-debug_dex2jar.jar

d2j-dex2jar.sh -f -o output_jar.jar apk_to_decompile.apk
d2j-dex2jar.sh -f -o output_jar.jar dex_to_decompile.dex

注1:在Windows机器中，所有的.sh脚本都被.bat脚本取代

注2:在linux/mac上不要忘记sh或bash。完整的命令应该是:

sh d2j-dex2jar.sh -f -o output_jar.jar apk_to_decompile.apk 

注意3:另外，请记住向dex2jar-X添加执行权限。例如sudo chmod -R + X dex2jar-2.0

dex2jar文档

步骤2:

在JD-GUI中打开罐子

自从这些答案被发布以来，很多事情都发生了变化。现在有很多简单的GUI工具，比如:

APK Easy Tool for Windows (GUI tool, friendly)
Bytecode Viewer - APK/Java Reverse Engineering Suite
URET Android Reverser Toolkit

找到他们最好的地方是在XDA开发者论坛上。