Question: If I use Amazon's Kindle Kids' Book Creator to upload to Amazon, does it allow download to all Amazon devices not just fire devices? I have a lot of illustrations and they get embedded so much better using the Kid's Book Creator than the Kindle tool.
All fixed format e-books (regardless of which software used) can be downloaded only on specific e-readers. A list of compatible devices is shown on the KDP help page. Additionally, they are difficult to read on many devices, especially those with smaller screens.