Three nit-picks. Firstly, no landscape support (this one's more than just a nit-pick, it's an issue). I'd like to see the borders removed on the details page, it feels out of place (especially how the Auto-Open Tab is separated like that. It feels like something from iOS). Just a 2dp dividing line between the header and the list items would probably work better (and maybe one more between Auto-Open Tab item and the others, but it's not really necessary). Lastly, the thumbnails on the Directory's list view should take up the full list item (see http://developer.android.com/design/style/metrics-grids.html#48dp-rhythm
) and don't need any padding.
Other than that it's gorgeous. I'm really impressed by the incredibly smooth transitions (and I'm not just talking about animations). It definitely respects and takes advantage of the platform.