Paul Laughton -  Original creator of Rfo-Basic (De Re Basic) for Android.
jMarc (former developer) - Rfo-Basic 01.91

(License)

Stefano - (x-quick-apk for linux)
Mougino - encrypt.jar.
aFox, Spike, dkal, Joel_Zerpa,,.. & others - various fixes & ideas.

CWAC document - DocumentFileCompat
A replacement library class to support Storage Access Framework.
https://github.com/commonsguy/cwac-document
Apache License, Version 2.0.

hpatcher uses widgets based on the work of the FLTK project
http://www.fltk.org

Zulu Enterprise
Apache License, Version 2.0.
(replaces Oracle's JDK)

Google Android SDK

diff and patch
GNU GPL
https://www.gnu.org/software/coreutils/coreutils.html

WinTee
Mozilla Public License 1.1
https://code.google.com/archive/p/wintee/

Vampyre Image Converter (library version 0.26.4)
http://imaginglib.sourceforge.net/
License: LGPLv2 or MPL 1.1

ftpServer
https://github.com/pReya/ftpServer
(no license specified)