Thanks, Filip, I have downloaded your (free) app - great shots! This one appears to be mainly pictures with captions; is that the same pattern in your previous (paid) apps?
I have been looking at options for online publishing, including ebooks, so I can control layout and text precisely. Although I have an iPad, I am not normally an Apple fan, and I do not like the constraints of the iBook format, which tie you, I believe to distribution only to iOS devices. I recently published a book on the Issuu platform http://issuu.com/paulashley/docs/colours_of_iceland
I like the presentation on Issuu, and the basic usage us free, but it is still relatively unknown as a platform.
I tried creating an ebook from Blurb, but Blurb's conversion tool is extremely limited and clunky: it wouldn't accept my choices of font, for example, and it was difficult to change fonts easily. I would like to create books in epub3 format, which allows good layout of images and text, but the best way to do this is with Adobe Indesign, which is expensive.
I'm still looking for the best online publishing option, and I will look at your app-creation approach.
Edit: if you follow my link to my book on Issuu, you will find it presents the book in a PC browser with neat page turning and zooming animation. These don't work in an iPad Safari browser (Issuu uses Flash) but there is an Issuu app that allows you to view Issuu books with a better user experience. I've never used Issuu from a Mac-based browser. (PS I have no connection with Issuu).