I am an amateur at using InDesign but have worked with a publisher to create an enhance eTextbook. The publisher uses CoreSource to export and format the InDesign into an epub3. Becuase of the enhanced interactive features the ebook only works in the Virtual Source Bookshelf app. In the Apple version of the app, when you click on a link to an external URL, you are automatically taken out of Bookshelf to view the webpage or web-based pdf in a browser (this is the way it should function). But in the PC and Android versions, clicking on the same link only works this way sometimes. More often, the link tries to bring up the webpage inside of Bookshelf, but the view is tiny and the webpage doesn't function properly (e.g., you can't even scroll down).
My hunch is that this is mainly an issue with the CoreSource conversion process or app. But I am wondering if there is a way within the InDesign file itself to set a preference for each link, similar to setting a preference for a link in a pdf to open a link in a new window or tab.
I welcome any direction someone might be able to give.