I'm attempting to make use of the UIDocumentInteractionController mechanism in iPhone OS 3.2, but I'm struggling to figure out exactly how to construct a UTI that it likes.

I've gotten as far as attempting to set "public.plain-text", but it's hard to test whether this is the correct UTI for a plain text document, since I can't tell whether the issue is that my iPad doesn't have any apps that support plain text import. (I figured Pages would, but I suppose perhaps not, since it will attempt and fail to load any files with the extension .pages, regardless of UTI).

Any seasoned OS X developers that can help on this?