Take a photo of a barcode or cover
Probably 2 1/2. Interesting idea. Fairly well executed. However, difficult to read. Didn't really care about the story in the margins and the story in the book was only mediocre. Lots of faux literary layers and a conspiracy that at the end you're not supposed to care about because "love". Which I find is how I feel about most things J J Abrams does so I feel a little bad for the guy who probably did the bulk of the writing.