You can't "right click" on iPad (or similar touch devices for that matter). The is where the "long touch" or "tap and hold" events come into place.
Say you want to have a context menu on a image. So you should bind (or delegate) a top hold event to that image that shows the menu.
In the event itself you should locate the menu, both in terms of object and HTML element; position it at the proper place and then show it.
All the best,
the Telerik team
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