With the release of high-resolution devices from all the major manufacturers, I have been musing on the possible development of high-resolution ebooks developed specifically for this market. These devices demand not only larger images but also a rethink of how image-heavy content must be delivered: just as we now see movies delivered in both HD (Blu-Ray) for one market and in standard DVD format for those without an HD system, I expect that we will start seeing HR ebook files developed for the high-resolution device market and differentiated from standard ebook files through title and ISBN identifiers.
We already see a differentiation in the market with the production of ePub3 and Kindle Format 8 fixed layout ebooks such as comic books, graphic novels, cookbooks, and many academic textbooks; and for regular ebooks with images, Amazon now want large image files delivered to them that Amazon then process into different sizes for delivery to different Kindle devices and apps. However, while Amazon can do this because theirs is a closed system, to address this same issue in the open ePub system would require that different files be produced: the HR files would crash many older ePub readers and apps, while images in regular ePub files are too small for the new devices. Thus I expect that ebooks that are text-centric but which contain images—such as manuals (like The Global Indie Author), history books, and personal memoirs—that are otherwise not suitable for the fixed layout format may soon need to be sold as two distinct ePubs, regular and HR.
In fact, I am currently writing the third edition of The Global Indie Author, and am contemplating producing a separate HR version. The stumbling block to doing so is that most of the images in the book are from software screen shots, which are by nature small to begin with, and would require specialized software such as Perfect Resize to bump them up to HR size, but the idea is percolating.