The standard ePUB and Amazon Kindle/Mobi eBook formats are so similar internally that we group them together. Almost all their configuration settings are identical, and because of this they can be configured with the same settings in your project's Configuration sections.
ePUB eBooks are a standard, generic and open eBook format that is supported by many software readers on all computer platforms and hardware devices, including the Apple iBooks® eBook reader on the iPad, iPhone and iPod Touch, Sony Reader and many others. ePUB eBooks are cross-platform and a huge number of eBooks are already available in this format.
Kindle/Mobi is the proprietary format used for Amazon Kindle eBooks, which can be read on the Amazon Kindle hardware eBook readers and a wide variety of Amazon Kindle apps on different platforms. Internally, this format is really just a minor variant of the universal ePUB format. However, Kindle eBooks are packaged in a proprietary Amazon binary format instead of in a normal ZIP file like standard ePUB. There are just a few formatting and configuration changes that need to be made and these are handled automatically by Help+Manual.