EPUB Reader
EPUB Reader › Guides
Google Drive has no viewer for e-books, so a book you keep there shows "No preview available" and your only option is to download it. EPUB Reader adds itself to Drive's Open with menu and reads the file in a browser tab instead.
Free. One Drive permission, the narrowest one Google offers. Nothing is uploaded and nothing in Drive is changed.
Install EPUB Reader from the Google Workspace Marketplace. Google asks you once to allow it, and it stays in the Open with menu from then on.
In Drive on the web, right-click any .epub and choose Open with → EPUB Reader. Double-clicking works too once the reader is the app for that file type.
The book opens in a new tab and joins your library in this browser, with your place, highlights, notes and bookmarks.
It asks for drive.file, the narrowest Drive permission Google has. That means it can open only the files you hand to it, one at a time, by picking Open with. It cannot list your Drive, cannot open anything else, and cannot change or delete what is there.
The file is downloaded from Drive into your browser and stays in the browser. There is no server of ours in the middle: the site is static files, so your book is not uploaded anywhere, not scanned and not stored by us. The copy in Drive is left exactly as it was.
Opening the same book a second time does not download it again. The reader keeps the checksum Drive reports for the file, and when it matches, the copy already in your library is used, so a big book opens instantly.
EPUB first, and also MOBI, AZW3, FB2, CBZ comics, plain text, Markdown and Word (.docx). Drive offers Open with for those types once the app is installed.
Yes: it downloads the file you chose into the browser, then reads it there. That is also why it works with no further requests once the book is open.
In your Google account, under third-party apps with account access, remove EPUB Reader; Drive's own settings list installed apps as well. Removing it does not touch your files.
Yes. Pro is a one-time purchase that adds unlimited read aloud, highlight export to Markdown and reading statistics; everything else works without paying.