I am formatting an ebook for a client who is quite particular about how it looks and displays on the device he uses, a newer iPad with Retina display. One of which I, unfortunately, do not have.
The current version of the ePub seems to display correctly in Calibre and ADE, my test apps, and it validates in my XML editor and the IDPF ePub validator. However, there are two glitches that show up only on the iPad: an extra blank page or two before a new chapter (sometimes but not always) and a cover image that works as a cover but is not picked up by the thumbnail-generating software. The book shows up on his iBook shelf with a generic cover.
One formatter over at Mobileread insists that he has tried many schemes to get rid of the blank pages and has given up. I think I give up too. I don't see what in my code, in the page-break-before:always that is part of the chapter .css, should be problematic. The client is willing to accept that the iPad just does that but ...
He wants the cover to be resized for a thumbnail. He sent me an InDesign epub that he said displayed properly as a thumbnail and a cover. So far as I can tell, my code is the same, save that I use a .jpeg file extension rather than .jpg for the image. The .jpg would not pass the IDPF validator. Also, I kept my cover .jpeg rather modest. It's 689x1000; his is 1890x2775. I think that is much larger than generally recommended.
(Peeve: ebook cover size recommendations are all over the place. I cannot figure out who to trust on this. I do not want to craft for one device and mess up the cover for other devices.)
I would appreciate hearing from someone else who has run into these problems, or at least one of them, and has come up with solution(s).