ClassExplorer

It’s easy to install, and once set up, it becomes a vital resource for understanding and documenting data structures. The ability to export diagrams as images is especially useful.

Very useful app to show IRIS class model in a UML class diagram style with all the inheritance and relationships.
A valuable aid to illustrate the IRIS object model ; very useful for education purposes.

The Class Explorer was easy to install : in fact, there are different ways to install, i choose to import the .xml file via Studio.
Once installed, the web interface was very intuitive to use, and there is also a video on this open exchange to watch a tour.
I had a problem where my license (Caché 5 users + web addon) was not sufficient for the various REST calls the web page is making. I did not notice it at first (only when i saw certain places of the screen were not filled with data, and looking at the json debugger, i noticed certain REST calls were not successfull).
To be able to solve it, you need to make the /ClassEplorer application use the Web Add on (by using the Event Class to make it public). Maybe this should be added to the install notes, or by displaying an error when certain REST calls fail.
But now that this is solved, I use the ClassExplorer to walk around my schemas and use it also to document the data structure for non-Caché/Iris users that need an overview of the available data.
A nice feature is that you can make images that you can use in other documents.