12 Differences Between EPUB and MOBI Ebook Formats

1. The full name of EPUB is Electronic Publication while the full name of MOBI is Mobipocket.
2. EPUB is an open standard format developed by International Digital Publishing Forum (IDPF) which is a global trade and standards organization while MOBI was developed originally by Mobipocket SA which is a French company incorporated in March 2000 for MobiPocket Reader which was later purchased by Amazon in 2005.
3. EPUB supports inline raster and vector images, metadata, and CSS styling.
4. EPUB can adjusts its size to suit different screens while MOBI is suitable for smaller screens because of an image file limit of 64K.
5. EPUB has a small file size while a MOBI is twice the size of an EPUB file.
6. EPUB has a file extension of .epub while a MOBI either has a .prc or .mobi file extensions.
7. MOBI and EPUB can display reflowable file content and fixed width layout.
8. MOBI has digital rights management (DRM) protection embedded on its file preventing it to be shared easily due to plagiarism issues while EPUB does not have digital rights management (DRM) so that it can be easily shared.
9. MOBI is a proprietary Ebook software of Amazon limiting its usage for Kindle books while EPUB is an open source software created by the International Digital Publishing Forum which can be read on almost all devices.
10. MOBI is created by taking an EPUB file, renaming, zipping, and extracting and using kindlegen.exe which is a proprietary Amazon program while an EPUB is created by placing all these files in a directory, namely a package .xml file, an OPF file, and XHTML content files, and then zipping all of it and using the .epub. filename extension.
11. You can use this link http://mobi2epub.com/ if you want to convert your MOBI ebooks to EPUB ebook format.
12. You can use this link http://ebook.online-convert.com/convert-to-epub to convert you files to EPUB format as well as several other ebook format.

References:

https://www.youtube.com/watch?v=kDf9XM1B0L8
https://www.youtube.com/watch?v=tliqZYGPUik
https://www.youtube.com/watch?v=BEcKYo32uM0
https://www.epubor.com/epub-vs-mobi-which-is-the-best-ebook-format-for-ereader.html
http://www.guidingtech.com/9661/difference-between-epub-mobi-azw-pdf-ebook-formats/
https://www.quora.com/What-are-the-differences-between-MOBI-and-ePub-Which-one-is-considered-best
https://www.quora.com/What-are-the-differences-between-ePub-and-Mobi-eBooks
https://www.cisdem.com/resource/convert-pdf-to-mobi-mac.html#EPUB vs MOBI
https://en.wikipedia.org/wiki/Mobipocket
https://en.wikipedia.org/wiki/EPUB