I rebuilt my project in Unity 4. It shows fine in the editor, in the web player, in the iOS Simulator. However, when I run it on my actual iPad it shows the Unity logo and then goes to a black screen. The strange thing is I can still interact with it in the background as when I click on places on the screen I can hear the associated sound effects.
I may be seeing something like this, but it’s just that any textures are missing. So I can see where things should be, but no image/textures.
UPDATED: For me it was a lighting issue - my light was washing out my images. I lowered the light and it worked. Not sure why it would be so different from Unity preview to iOS???