Import, export, account deletion, and how to reach a person.
Goodreads only lets other apps do this by file, which is why it is two steps rather than a single button. StoryGraph and LibraryThing exports work the same way. Books already on your shelves are skipped rather than duplicated.
Library → Add a book → Export. You can take a spreadsheet that any other reading app will accept, or a full backup file. Worth doing occasionally.
In the app: Profile → Settings → Delete my account. That removes your profile, library, reading history and messages. It cannot be undone, so export first if you want a copy. If you cannot get into the app, email us from the address you signed up with and we will do it for you.
Tell us what you were doing and what happened, and include the small version number in the bottom-left corner of the app — it tells us exactly which build you are on.