Also what is this "advanced epub" format they have? I can't see where they describe the actual difference with "compatible epub".
I use [Librera Reader](https://f-droid.org/en/packages/com.foobnix.pro.pdf.reader/] and [Voice](https://f-droid.org/en/packages/de.ph1b.audiobook/) for audio books.
[KO-Reader](https://f-droid.org/en/packages/org.koreader.launcher.fdroid...) is also recommended, but the one above I found easier to use, though both seem highly recommended.
I found these Android apps from this [post on r/androidapps](https://old.reddit.com/user/Jackie7610/comments/lr5gag/list_...)
Basically just look for epub, as that is the open standard - though really it doesn't matter if you use [Calibre](https://calibre-ebook.com/) as it can convert between them, but you have to check the types supported yourself...
> Also what is this "advanced epub" format they have? I can't see where they describe the actual difference with "compatible epub".
They have [an explanation here](https://standardebooks.org/help/how-to-use-our-ebooks#which-...), but I would say, when in doubt, just go with the compatible one.
Besides, it's just a book, I doubt anything will explode if you use the wrong the version...
The "advanced ebook" is not displaying the cover, I'll reach to the dev, but the compatible version is ok.