What is the difference between EPUB and MOBI
The core difference between EPUB and MOBI is that EPUB is broadly supported on all platforms, while MOBI is mostly a Kindle format. EPUB can display “Reflowable” content that will fit your presentation to the output devices, as well as a fixed-width layout. MOBI formats can handle complex content, contain advanced navigation controls, support indexing, and handle a high level of compression. Like EPUB, MOBI can display both reflowable content and a fixed-width layout.

The core difference between EPUB and MOBI is that EPUB is broadly supported on all platforms, while MOBI is mostly a Kindle format.