Where possible, there should be keyboard shortcuts/navigation.

Where appropriate, the labeling of fields and so forth should be such that it will work for a screen reader.

Often, the expedient option is to use an HTML front-end so that one can off-load most of that to the user's selection of web-browser (and where possible, things should be engineered so that Lynx is a valid option).

That said, I use OneNote and Macromedia Freehand and so forth w/ a stylus --- horses for courses.