I've been working on Apologue each evening this week. And a lot of progress has been made. When I began working on this I had just finished putting together the skeleton of a user interface, which was very rough. It consisted of a code editor, and a stack display (which was literally just a text representation of the stack items in a text area).
Now it's grown into a much more complete tool. I have an editor view, with the code editor, stack display, and a status/error log area. There's a memory browser which lets me browse the named symbols in the dictionary or any allocated slice, viewing the raw values, ASCII values, and byte codes for each item.
I also have begun a documentation browser, though it's still very sparse at present.
Overall I'm pretty pleased with it. There's a lot of stuff I still want to do, but it's working well enough that I can do most of my Parable experiments on my iPad now. In the near future I'm planning to expand the embedded documentation to cover everything I've written so far, make a few further improvements to the memory browser, and enable persistent sessions so that I don't have to manually reload/evaluate to continue where I left off.