I have published a beta version of my children´s book about the music detective. I have used Hype to create the widget for iBooks author, and published through apples service. The user is supposed to tap some musical notes that runs across the screen (on the third page in the story). This works on iPad, but not on iPhone 6/6s.
Here is the book. Tap the small thumbnail in the bottom left corner of the first scene to start the book.