We have just reproduced the issue. Alas, there is no simple fix for this bug, as the editor uses an iframe and iOS tries to show all its content. We have logged this for further investigation.
A work-around for this is to set the width of the body element in the iframe, like this:
var editor = $("#editor")
editor.data("kendoEditor").body.style.width = editor.find("td:last").width() + "px";
Please note that this width should be updated on every window resize / orientationchange.
Your Telerik points have been updated for the bug report.
All the best,
the Telerik team
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