When I load one of my books in my Kindle app on iOS, it goes to the back of the book instead of going the cover / beginning. What can I do to fix this problem? Thanks.
In the toc Nav element add a Landmark called Begin and point it to the first page that starts the book. A landmark to the Cover is also an option.
The Kindle app for iOS is optimised for readers, not development or proofing, which is important to keep in mind for some things, like this. The reading position is set as you read the book (because that is what all readers want), so if you happen to navigate to the end for any reason, it might mess that up.
The start point in the Windows version is hard-coded, and that is what it should always open to when using a reference viewer, like Kindle Previewer on your computer. It’s not the most comfortable environment for reading, but for proofing design, layout and navigation, it’s the main tool that should be used. Hardware testing is good, but you just have to keep those things in mind, that it’s optimised for readers. Cover thumbnails may not update, and things like that, because it caches those to make the software fast.
And by the way, Kindle Previewer has an exporter for iOS sideloading, that you should be using instead of Mobi anyway (if that’s what you’re doing). The iOS version doesn’t read the .mobi format well, and it isn’t fully supported. Maybe you are seeing a side-effect of that.