[topic moved to Reader/Acrobat DC for Mobile forum]
Here's an old blog post regarding 3D PDF Support on iOS.
Please note that the app (3D PDF Reader) is not maintained by Adobe. The third-party app is still available from the Apple App Store. But the app has not been updated since November 2013.
Unfortunately, we are not able to speculate on any future product plans or release dates in the public user forum like this. Sorry for the inconvenience.