Nothing is uploaded by default. Books you add are held in
this browser's own storage, together with their covers. A book leaves this
device only when you choose Synchronize, and then only to a folder
in your own Google Drive.
The reader is free, and supported by advertising. Adverts
and the measurement of them use cookies and similar storage, and so does
the analytics that tells us what is broken. What your books contain, and
the marks you make in them, are never used for either.
Signing in is optional. If you do sign in with Google, where
you got to in each book, your highlights, your bookmarks and your shelf
marks are kept under your account so your other devices agree with this
one. Without an account the reader works in full, here.
You can have that data deleted at any time — write to
librera.reader@gmail.com.