I find it very useful in that it gives me access to the 10 (4 on iPhone) most recently opened books, regardless of the books' Library folder. So, Marvin's Home screen is a useful
virtual folder, and because it's so colourful, it's visually pleasing, too.
My pleasure in using it is only spoiled because Marvin does not currently remember its position between app relaunches (see
here). Once I'll be able to rely that when I abandon Marvin on the Home screen, Marvin will launch on the Home screen next time as well, then the Home screen will become even more useful. (Naturally, on
other occasions, I wish to abandon Marvin while reading a book, and for that book to be launched directly upon next Marvin launch.)