(that's "catagories" of course, the title got too long)
The title says it all, when I select a category I can't get back to the list of categories by tapping on "Categories" again. Usability-wise I would expect to go back to the list, because the button gave me that list the first time. :)
I don't think it's relevant, but my list of test devices: Moto G/Android 4.4.2, HTC One V/4.0.3 and Nexus 7/4.4.3. All stock unmodified non-rooted. ROMs.
I assume that this is specifically in reference to the tablet interface where the navigation sidebar is visible all the time? We haven't designed 1Password to function in the way that you describe above, but I can certainly pass along the suggestion to our development team.