Hi Jennifer
The Fixed Layout EPUB3 standard *allows* some really cool features to be included in a valid EPUB3.
However… not all device and reader makers can/will support them.
It is obviously not an ideal situation and the https://epubtest.org attempts the unenviable task of keeping track of who supports what to make sense of all the different support but in the fast paced world of digital publishing it can be found to be dated and patchy…
In short though:
Apple iBooks and Readium are the one ones with best support for most features.
Adobe Digital Editions and Kobo are usually quite good too and worth a look.
Google Play supports the ‘simple’ stuff quite well, such as displaying pages but can’t handle much animation or any audio, video or read-aloud media overlays.
And if you are looking for any Amazon support for this kind of stuff – forget it!
Hope that helps…
Ken
Ken Jones
Director
Circular Software Limited
circularsoftware.com
CircularFLO – make read-aloud EPUBs from $99