Apple says this can be a reason for rejection for any Iphone app:
No Interpreted Code You cannot create an app that downloads and executes code that was not present in the app bundle submitted to Apple.
Downloading and running Html code from my web service to iphone is forbidden ? Please no guessing but real experience.
Apple means the following with their rules:
What you can do:
website
UIWebView
What you can’t do:
it. (wouldn’t work as they’re probably unsigned, but Apple rejects apps that do so anyway)