https://ibotpeaches.github.io/Apktool/install/
$ apktool
Apktool v2.6.1 - a tool for reengineering Android apk files
with smali v2.5.2 and baksmali v2.5.2
Copyright 2010 Ryszard Wiśniewski
Copyright 2010 Connor Tumbleson
usage: apktool
-advance,--advanced prints advance information.
-version,--version prints the version then exits
usage: apktool if|install-framework [options]
-p,--frame-path <dir> Stores framework files into <dir>.
-t,--tag <tag> Tag frameworks using <tag>.
usage: apktool d[ecode] [options]
-f,--force Force delete destination directory.
-o,--output <dir> The name of folder that gets written. Default
is apk.out
-p,--frame-path <dir> Uses framework files located in <dir>.
-r,--no-res Do not decode resources.
-s,--no-src Do not decode sources.
-t,--frame-tag <tag> Uses framework files tagged by <tag>.
usage: apktool b[uild] [options]
-f,--force-all Skip changes detection and build all files.
-o,--output <dir> The name of apk that gets written. Default is
dist/name.apk
-p,--frame-path <dir> Uses framework files located in <dir>.
For additional info, see: https://ibotpeaches.github.io/Apktool/
For smali/baksmali info, see: https://github.com/JesusFreke/smali