To free up space on your device's storage, erase all unneeded or unwanted books and audiobooks. Here's how you do it:

1. On your iPhone X, open iBooks.
2. Select the one you want.
3. Scroll to the book or audiobook you wish to remove and select it.
4. To choose an object, tap it.
5. Then choose Delete.
6. If you simply want to erase the item from your iPhone X, choose Remove Download.
7. If you wish to delete an item from iCloud and have it immediately removed from all of your other devices, choose Delete Everywhere.

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