I find reading books on a midsize tablet (~ 7 inches) convenient and enjoyable. The ability to easily carry the book in my purse everywhere compensates for the downside of not remembering author names and book titles anymore (simply because the cover of the book, and hence the author name and title are virtually never seen when using a book reader). But, in spite of repeated attempts, I was never able to use digital formats for reading nonfiction books.
You may be wondering what makes fiction books different than non-fiction ones. The answer is sequential access: most fiction books are made to be read page by page, in order, from the beginning to the end. Historically, fiction was a successor to listening to an oral performance — like the Iliad — and 2,800 years later storytelling still seems to work best in a linear manner where readers can absorb the flow of the author’s progression through the story.
You rarely jump from one chapter to the next in a fiction book, and if you are tempted to do so, ebooks do a great job of deterring you by making it so difficult to come back. With nonfiction books and textbooks people need to go back and forth, refer to charts and illustrations, jump from one chapter to another, and generally be able to easily find their way into the book. Sadly, modern general-use book-reading apps (such as Kindle or iBooks on iPad) support that task poorly.
Impoverished Hyperlinking
You’d think that the electronic medium would be ideal for books that need lots of footnotes and annotations: the reader could in theory access these annotations in context, without having to go to the end of a book or squint to read the small footnote text as it is often the case with a regular book. To my disappointment classical texts such as Shakespeare’s plays have very little electronic support. Most versions available do not support annotations, or, when annotated, risibly follow the limitations of the paper medium, as in the screenshot below.
Custom sections that can be optionally read by those interested can be easily supported through hyperlinks, yet ebooks still have to take advantage of it. A “spoiler alert,” for instance, is unnecessary: instead the spoiler text could be placed on a separate page, accessible through a hyperlink. By inserting it in the text, the editors force the readers to go through those spoiler pages until they find the spot where they can continue reading.
A different type of specialized book app departs more from the physical-book mental model and does a better job with annotations and notes than both Kindle and iBooks. An example is the Museum of Modern Art (MOMA)’s “Picasso: The Making of Cubism 1912-1914” which is “the Museum’s first digital publication” (according to MOMA’s webpage). The MOMA app uses popovers to conveniently show notes in context. Most of the time the note text is good enough and the user can resume reading right away after reading the note. However, occasionally, some of the notes send the user to special sections of the chapter (e.g., Provenance) without implementing the link. This is unfortunate: the designers should have made it easier for the user by providing an actual hyperlink to the relevant section in the book.
The MOMA app is also careful at minimizing the interaction cost and the working-memory load: all the figures referred on a page are carefully shown as thumbnails on the left hand side, so users do not need to browse back and forth through the book in search of the corresponding illustration, nor do they have to memorize the context in which the figure is discussed. Unfortunately, they still have to identify which figure on the side corresponds to the reference in the text, and tap on that figure for more detail. (The text uses bold bracketed numbers to refer to the corresponding figures on the side; thus “[2]” refers to the figure labeled “2”. However, the bracketed numbers in text are not links: people cannot tap on them and automatically see a larger view of the figure. Instead, they have to go to the list of figures, find the corresponding picture in that list, and tap on it. Just that much more work for the user to match two numbers instead of tapping on one.)
The Back Button in iOS Book-Reading Apps
Once the hyperlink is present in the text, a Back button becomes mandatory: if you can jump from one section of the book to another, you should also be able to find your way back. Because, unlike Android tablets, iPads do not have a built-in Back button, the interface must accommodate this functionality.
Both iBooks and Kindle treat the Back button as a dirty little secret: they don’t want you to know it’s there. Can you find the back button in the following screenshot from Kindle for iPad?
If you guessed the small blue arrow in the bottom left corner, you were right. The button is tiny and placed in a nonstandard location — at least for iOS. (Android users are more used with the physical Back button being at the bottom of the screen, although not necessarily in the left corner, as the position can differ from device to device). Plus, it’s invisible most of the time, and, to make it visible, you must tap the screen: by default the chrome is hidden to maximize the content area, and the tap gesture exposes all the UI on the page.
Even though the technology for going back in the book is available, the Back button is so buried in the interface that the chance of discovering it is minimum. The little blue arrow is close to the page slider, an interface widget that people rarely use in an ebook since it’s so imprecise.
When it comes to a Back button, the MOMA book fails spectacularly: it doesn’t have one at all. Presumably, since the notes and illustrations keep users in context and don’t move them to a different section of the book, the designers decided that they don’t need a Back button. Wrong! Even if your app does not provide hyperlinks per se, any textual reference to a different section of the book (such as See Provenance note 2) is in reality a hyperlink that users have to implement by hand. If they really care about that provenance note, they will go and check it out, and then will have to find their way back to the text that they were reading.
Poor Illustrations
Textbooks and other non-fiction books frequently supplement text with figures, tables, and images. These are essential learning tools, but, somewhat paradoxically, their deployment in digital books is suboptimal. From the beginning beautiful images on high-resolution screens were a tablet strength, yet the illustrations found in ebooks are often low resolution and look unappealing. And the interactions around figures and tables are cumbersome. For instance, many times figures are shown on a separate page than their captions or tables may be split across several pages. (The ability to change the font may interfere to some extent with a fixed layout where the caption is never separated from the image; yet, at least in the default font size that most people will use, the figure and its caption should be on the same page.)
In our original iPad study from 4 years ago users were deploring the inability to zoom into pictures in the iBooks app. Things have changed: in both the iPad and the Kindle app, people can now tap on an image to see a larger view of it; in that view, they can then zoom in and out as needed. But in the image view, users cannot see the image caption anymore: they have to recall it to interpret the figure.
MOMA does take good advantage of the tablet’s screen resolution and digital medium. It enriches text with photographs that don’t easily find space in a printed book (for instance, face and back of a painting, or X-ray photograph of a sculpture), as well as videos and 3D renditions of sculptures. The MOMA app does preserve captions for illustrations in image view, but does not always properly utilize the space for rendering an image. For instance, when looking at an digital art book, it’s important to see the paintings themselves as big as possible to mitigate for the smaller tablet size compared to that of a regular art book. It should also be possible to use zoom to enlarge details of interest several times over: one of the main benefits of a tablet compared to a printed book is that images aren’t constrained by the cost of printing more color pages. However, the sizes of the images in the Picasso ebook are surprisingly lower than the available space, both for paintings that form the subject of the book and for references from the text.
Conclusion
As any college student will certify, lugging around a backpack full of books is no fun. Digital books are light and convenient, yet they still leave much to be desired in terms of usability. Even though an app is not a website, you should still support the main hypertext and navigation features users have come to expect. Publishers and designers of book apps need to take the extra step and consider (1) better capitalization of the digital medium by supporting in-text hyperlinks and easy navigation; (2) high-quality, self-contained illustrations with a high level of detail.
