You should only delete books on your device when you are experiencing syncing difficulties despite having a stable internet connection. Synching problems can prevent your access to the latest media overlays and annotations like comments, highlights, bookmarks, or scribbles. Deleting the book and re-downloading it should be considered a last resort.
We do not recommend deleting books from your device in other circumstances as you might lose the annotations you have made in the book.
How to Delete Books from your iPad
1. Login to TextBookHub on your iPhone.
2. Go to “My Bookshelf” and select the book you wish to delete by tapping on the book cover.
3. The book detail panel opens. Tap on the pink Delete button.
4. Your book has been deleted from your device. Notice that the deleted book no longer has a green checkmark in the upper left corner of the cover.
NOTE: You can get your books back again by re-downloading them. Look here to learn how to download your TextbookHub books.