Sorry, but I don't have an iPhone to test. I tried using Safari Web Inspector on my Mac, but I'm not able to select mobile safari in the user agent to simulate. The html page is not published on a server in order to run it through a browser outside of my Mac. The code is validated and tests fine on my Mac and on Adobe Content Viewer on iPad first generation. How can I resolve? Thanks.
If it's testing fine on the iPad1 this really speaks to a difference in the OS handling of the HTML. It's not, unfortunately, a DPS thing, and it's not a fun thing to chase down. Perhaps some people here will have some debugging tips.