PDA Toolbox - Powerful WYSIWYG development platform. - http://www.pdatoolbox.com/
NS Basic - A complete development environment for all skill levels. - http://www.nsbasic.com/palm/
LispME - A Scheme (Lisp) version for the PalmPilot with related files, such as Parentheses Hack. - http://www.lispme.de
OrbForms Designer - A complete development tool combining a visual form designer, a smart code-completing source editor, and a rich object-based API. - http://www.orbworks.com/
AppForge - Microsoft Visual Basic add-in for handheld programming. - http://www.appforge.com/
Winsoft Ltd - Pascal compiler and IDE for the Palm. - http://www.winsoft.sk/
Fred Bayers LispMe - Information about LispMe, a Scheme (Lisp) version for the PalmPilot. Includes useful related files, such as Parentheses Hack. - http://www.lispme.de/lispme/
Palm: Software Development: Alternatives to C - Descriptions and links to the many languages and development kits usable for Palm programming. - http://goanna.cs.rmit.edu.au/~winikoff/palm/dev.html
Quartus Forth - Native-code Forth compiler-interpreter for Palm Computing Platform. By Neal Bridges. - http://www.quartus.net/