iBooks Author: Enable an object to be viewed larger in iBooks
You can enable readers to temporarily maximize the view of images, shapes, tables, charts, and text boxes in the completed book.
Enable an object to be viewed larger
Select a floating or anchored image, shape, table, chart, or text box.
Note: To enable an inline object in a portrait or landscape template to be viewed larger, change the inline object to a floating or anchored object.
To set the object to be viewed full-screen when readers tap or click it, select the “Goes full-screen” checkbox.
To display the object as a thumbnail image that maximizes when readers tap or click it, select the “Uses thumbnail on page” checkbox (in portrait or landscape templates), then do either or both of the following:
Continue to edit the object: Select the thumbnail image, click Edit Frame, make your changes, and click Done.
Change the thumbnail image: Drag a new image to the thumbnail.