For example, "Geeza Pro" is listed in both the native app drop down menu (IBA) and iPad fonts list. But when I used it in my book and previewed it on the iPad, Geeza Pro didn't show. It was substituted with a different sanserif font.
Geeza Pro is only for use in producing Arabic language text.
There are many fonts for languages other than English available. Best not to use them for English.
(PS: It may seem like you are using Geeza Pro for English in OS X, but you are not, the OS automatically uses another font which does have Latin characters without telling you)
I'm having a similar strange situation where I set the alignment and character spacing in iBooks Author and it appears the way i want it but when i preview on my ipad the spacing and alignment don't hold up. I then did a .pdf preview and the spacing was how I see it in ibooks author (i.e. correct). Is this a bug? Should I be concerned? I certainly dont want to publish something that when finalized doesnt appear how it should. Any ideas? thanks in advance!
note: by the way, I'm using the Kailasa font in this case...