Moved to InDesign epub forum./
What version of InDesign?
It's CC 2014
Did you save as MP4 (H264 encoding)? Did you save as EPUB 2 or EPUB3?
MP4 (H264) and EPUB3 works for me on my iPad and iPhone.
I have tried to export to epub 2 and 3. The video is MP4 (h264). It was working just fine on all devices now I can't seem to get any video to export and work.
Pretty sure it all stopped working after the Yosemite upgrade on the Mac or iOS 8 on devices. Or maybe both.
Oddly, it plays in iBooks on my mac, just not on the iPad or iPhone.
I've also tried to just export a couple of short test epubs with vids in different formats but get the same result....not working.
Are you on InDesign CC 2014 or 2014.1. What is exact iOS version on your iPad. Can you please send me (firstname.lastname@example.org) one of the packaged indd file in which you are seeing the issue. It will help in reproducing the issue.