ePub is basically just a limited HTML page in a zip file (plus a bunch of metadata and CSS styles), and ePub 3 can contain audio and video elements embedded in the text, just like a webpage. With the most basic usage, it would just show up as an audio player in the middle of the text, no sync. But there is also a media overlay thing I haven’t looked much into that looks like it provides sync.
What is the difference between an audiobook and an audio epub? Does the latter contain both text and audio? Are they synced somehow?
ePub is basically just a limited HTML page in a zip file (plus a bunch of metadata and CSS styles), and ePub 3 can contain audio and video elements embedded in the text, just like a webpage. With the most basic usage, it would just show up as an audio player in the middle of the text, no sync. But there is also a media overlay thing I haven’t looked much into that looks like it provides sync.