Amazon has announced that all of the modern Kindle e-readers will support the most popular ebook format in the world, EPUB. The company recently updated their Send to Kindle documentation and stated that it will add support for EPUB later this year. Send to Kindle will suspend the ability to load in MOBI, since it is an older file format and won’t support the newest Kindle features for documents. If you have MOBI books already on your Kindle, they will continue to be accessible. Amazon is also disabling to the ability to send AZW to the Kindle.
Send to Kindle is a very underrated system to send files to supported devices registered to your Amazon account. You can send books, PDF files and other supporteed documents to your e-reader. Most people send files as attachments in their favorite email client, such as Outlook, GMAIL or even Hotmail. You can send the documents from your main email account and the TO address is your special Kindle email account, you can learn about this feature in their official help file. Send to Kindle also has a dedicated app for PC and MAC, in addition to a Google Chrome Plugin. In order to send EPUB books to your Kindle, they have to be DRM-Free, so the books cannot have any encryption.
I think the first big step towards wide adoption of EPUB is to integrate support into the existing Kindle reading system on E INK devices and then the main Kindle app on Fire tablets. This is actually easier now, than before. This is because Amazon is in the middle of changing their existing Java framework to React Native. This is likely why they are waiting until Fall or Winter 2022 to add in support for sending EPUBS to the Kindle and for them to be read, instead of covertly converting them from one format to another.
There are many questions about Kindles supporting EPUB. Will publishers and independent authors be able to submit EPUB files and sell them on Amazon? Will Amazon use their own encryption and metadata, or will they will buy a license from Adobe? They could possibly do, what Kobo has been doing for a number of years. Kobo uses EPUB, but their files are called KEPUB, this is due to Kobo readers having an SQLite database that helps them read and manage books that come from their bookstore or another bookstore that has adopted their format. In some cases the books downloaded from their web store will be stored directly in this database and in other cases the books will be stored separately but will be referenced and managed from the database. Regular EPUBS support uses Adobe’s RMSDK engine while Kobo KPUB uses NetFront’s ACCESS engine. I think Amazon will likely use their own EPUB system, and maybe called it AEPUB.
Update: It looks like Amazon is converting the uploaded EPUB to KF8 (AZW3). So, it looks like they might not support EPUB natively.