If you are design-oriented, you want to have total control over how your layout looks when it is viewed on an electronic device. For this you use a fixed layout format. With fixed layout, your images display in the background and your text sits “on top” using absolute positioning.
One reason for using Amazon’s Kindle fixed format (referred to as the Children’s book format) is the fact that the book you produce can be viewed on any device having the Amazon reader application. This includes the iPad. Also, Amazon’s Previewer application makes it easy to preview what your book will look like when viewed on the Kindle Fire and eInk devices.
Even though Previewer has Kindle for iOS listed as a Device for preview, this only applies to dynamic format books. So how do you preview what your fixed layout book will look like on the iPad? The answer is, you don’t. So you wait, and pray until your book is actually published. Then, you can view your book.
The Bottom Line:
If you do decide to publish an iPad version (by not electing to use KDP Select or by waiting until the pre-determined period of exclusivity has lapsed), you then have several options.
As long as you are going to the trouble of signing up with Apple and going through their publishing process, you might as well add more functionality to your book. For this you have three options: