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If you’ve tried sideloading content onto your Kindle you’d quickly discover a number of limitations – including the inability to use the popular ePub file format. That’s all changing with the current crop of Kindles because Amazon is phasing out mobi file support and adding ePub support to its email-to-Kindle service.
This may seem like a small change but it’s been a serious pain for many fans of the ePub format. Writes Amazon:
Thank you for using the Send to Kindle service to send personal documents to your Kindle library. We wanted to let you know that starting August 2022, you’ll no longer be able to send MOBI (.mobi, .azw) files to your library. Any MOBI files already in your Kindle library will not be affected by this change.
MOBI is an older file format and won’t support the newest Kindle features for documents. Any existing MOBI files you want to read with our most up-to-date features for documents will need to be re-sent in a compatible file format.
Also, compatible formats now include EPUB (.epub), which you can send to your library using your Send to Kindle email address. We’ll also be adding EPUB support to the free Kindle app for iOS and Android devices and the Send to Kindle desktop app for PC and Mac.
The service works now and the mobi shutdown will happen later this summer.
