Decompiler for "apk", "dex", "jar", "class" files. This is a android adapted version JaDX (https://github.com/skylot/jadx). Also this program used FileDialog library (http://code.google.com/p/android-file-dialog/). The program does not decompile xml files and other resources, only classes.
Source code is available here https://github.com/NaikSoftware/jadx