OnClientModeChange event is not fired in Mobile RenderMode. Steps to reproduce: Run the following code in a mobile Chrome (or mobile emulation) and click the edit Pencil button that switches the edit modes: <script type="text/javascript"> function OnClientModeChange(editor, args) { var mode = editor.get_mode(); switch (mode) { case 1: alert("We are in Design mode"); //do something break; case 2: alert("We are in Html mode"); //do something break; case 4: alert("We are in Preview mode"); //do something break; } } </script> <telerik:RadEditor runat="server" OnClientModeChange="OnClientModeChange" ID="RadEditor1" RenderMode="Auto"> </telerik:RadEditor>