Currently we have been implementing different improvements related to the RadMenu control and touch devices. The behavior that you encounter is an intended one and should be observed only on mobile devices running Windows8 and not on desktop machines. The current behavior of the RadMenu under mobile devices is to show its children upon touch(click), since other devices such as iPad or tables running Android does not use docking keyboard as the Surface for instance. We are still gathering feedback regarding this new behavior and whether it's applicable for users with Windows8 tablets. As for a "fix", I could try to provide an override, but please keep in mind that there will be an usability problems if the user tries to use the menu without keyboard and with touch gestures only.
However, lately we found an issue related to the RadMenu when used with devices that support both touch and mouse over events. Can you clarify what is the device that you are testing on? For some more clarification the reason for the experienced problem is the fact that laptops with touch screens are recognized as a mobile devices. We shall try to fix this problem as soon as possible, but until the fix is ready please use the override provided in the attached sample page.
the Telerik team
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