> On consumer devices, picking through file hierarchies is a lot more
> painful due to input method limitations. The use cases of such devices is
> also fairly different.
I've not found picking through file hierarchies that much more difficult on my Android tablet (WinTec Filemate Identity), in those apps such as CoolReader that expose it. On the other hand, the built-in Gallery app goes through my *ENTIRE* filesystem, and finds all of the cover image thumbnails from my e-books, and presents them as a flat view of folders for each directory that contains an image - but doesn't preserve the fact that those folders were already in folders to group them together.
Frankly, it's asanine, and I hate it.
If people have too damned much trouble understanding folders in folders, then have your app display a file drawer for a folder containing folders, a filing cabinet for a folder containing file drawers (to be cutesy, stack the folders that aren't in subfolders on top of the filing cabinet...), and a file room for containing filing cabinets.
Those kinds of people are not all that likely to be working more than 4 levels deep, anyway.
(I hereby dedicate the idea of icons of file rooms, file cabinets, file drawers, and file folders, used to indicated different levels of containment, to the public domain - or I would, if it weren't so bloody obvious it should legitimately already be in the public domain!)