Nice interface with an intuitive idea, but needs a lot of work. It fails to detect clearly visible faces in many pictures and does not even allow for manually selecting a face. Once it doesn't detect faces in a picture, you can't do anything. At least provide an option to manually pick faces. The other problem is that the pictures from all your albums are lumped together in one camera roll, without separating them into albums like every other app does. This makes photo selection extremely awkward.