The open ebook standard nearly every e-reader supports — except the one made by the company that sells the most ebooks.
EPUB (Electronic Publication) is an open ebook format built on the same underlying technology as a webpage — HTML and CSS — packaged into a single file so the text can reflow to fit any screen size rather than staying fixed on a page the way a PDF does. That reflowable design is what makes EPUB genuinely comfortable to read on a phone, a tablet, or a dedicated e-reader: font size, line spacing, and even the color scheme adjust to the device and the reader's preference instead of forcing a zoomed, panning view of a fixed layout. Apple Books, Kobo, and most e-reader hardware outside of Amazon support EPUB as their native or primary format, which makes the one major holdout notable: Kindle devices do not read EPUB directly, requiring either a conversion or Amazon's own format instead, despite EPUB being the more open, widely adopted standard across the rest of the ebook world. A reader who needs an EPUB as a fixed, page-accurate document instead — to print an excerpt or archive it exactly as laid out — converts it to PDF.
iPhone, iPad, and Mac open EPUB natively in Apple Books. Kobo and most other dedicated e-readers support it as their native format. Kindle devices and the Kindle app do not read EPUB directly — Amazon uses its own ebook formats instead.
EPUB's reflowable text is comfortable to read but not fixed enough for printing or exact-layout archiving, and it does not open at all on Kindle hardware without a separate conversion step. Filemorph converts EPUB to PDF on-device when a fixed, page-accurate version is what's actually needed.
Filemorph can convert EPUB to PDF on-device — a fixed, page-accurate layout for printing or archiving, instead of EPUB's reflowable text.
Filemorph converts .epub files entirely on-device on iPhone, iPad and Mac — no upload, no account, and it works in Airplane Mode.
Relevant operations in Filemorph:
Kindle devices and apps use Amazon's own ebook formats rather than EPUB, even though EPUB is the more widely adopted open standard across the rest of the e-reader market — Kobo, Apple Books, and most other readers support it natively.
It means the text rearranges itself to fit whatever screen it's displayed on, adjusting line breaks and page boundaries to the device's size and the reader's chosen font size, rather than staying fixed the way a PDF's layout does.
Yes. Filemorph converts EPUB to PDF entirely on-device, so an ebook file never has to be uploaded anywhere to get a fixed, printable version, and the conversion works with no internet connection.