Add links to text or objects.
You can create a hyperlink that refers to any page within your book (i.e. publication). Page hyperlinks from portrait pages have to navigate to another portait page, and hyperlinks from landscape pages have to navigate to another landscape page.
You can create a hyperlink that links to an external URL. On the tablet, tapping such a link will open a browser popup window for that URL within the app. Once the user has finished using the browser, tapping the "Done" button of the browser popup will bring the app back to the foreground.
Although in most cases, you want to keep readers in the embedded browser, sometimes you may want to open a link directly in Safari on iPad or in the default browser on Android. A good use case for this is if you want to link to a PDF that you want readers to be able to download.
You can do this by adding an extra parameter to your URL:
The URLs below will open in the embedded app browser:
And these will open in the device browser:
Embedded content will always be available, even when a user is offline.
Once you have copied all your html content and assets to that location, enter the Destination URL in the hyperlink field as shown below:
You can create a hyperlink that links to an email address with an optional subject. Tapping such a link in the app will open a mail popup window to that email address and optional subject. Once the e-mail has been sent, the app returns to the foreground.
For more advanced info about mail links, see this article: Mailto hyperlinks
If you want to turn text information into a hyperlink, it may seem logical to select the text in the text block, then turn it into a hyperlink. Depending on the point size of your text however, you may decide to place a transparent rectangle on top of the text and attach the hyperlink to that, so you can be sure the tap target is big enough (Apple recommends a minimum size of 44 x 44 pixels for such targets).