while an iframe may be a convenient way to display content, you should keep in mind that it has a lot of limitations and downright weird behaviors and restrictions in iOS. For instance, the ifame will always stretch to display all of its contents, ignoring the size setting. The iframe itself cannot be scrolled, too.
My advice would be to experiment a bit with that approach while testing on an iOS device. the behavior I describe is not related to or caused by Kendo UI Mobile - you should be able to reproduce it in a very simple scenario (a simple document with an iframe would do).
You can find more info about the issues I refer to in the following stackoverflow thread
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