I'm in the same boat. I embedded youtube videos to a jw player playlist and it's not showing on ios devices. I've reached out to Long Tail and am a premium member, but still haven't heard back. Their support has been nonexistent.
We have Woo Commerce and a child theme for Canvas running on a site that also has a video page using JW Player. We are not able to see the player on mobile devices (iPhone) and iPads, even though the player is setup to be HTML5. http://reedsinc.com/videos/ is the page.