GPG
http://www.gnupg.org/
http://en.wikipedia.org/wiki/GNU_Privacy_Guard
http://zh.wikipedia.org/wiki/GPG

GPG4Win
http://www.gpg4win.org/
http://en.wikipedia.org/wiki/Gpg4win

AGP:
1 23
http://en.wikipedia.org/wiki/Android_Privacy_Guard
https://code.google.com/p/android-privacy-guard/downloads/list