You demos are all set to a max displaysize of 1023 px by below lines:
@media screen and (max-width: 1023px) {#pivotgrid,#configurator { display: none;}}
On your release webinar on YouTube you are very proud of the easy responsive design of Kendo UI, but i couldn't find a way to make the PivotGrid responsive.
Did i miss something? The demo (dojo) on mobile phones doesn't show anything.
4 Answers, 1 is accepted

Cory Sevigny from Telerik told me that the PivotGrid is not responsive yet because in most cases it's not used on mobile devices.
Therefor i added a feature request:
http://kendoui-feedback.telerik.com/forums/127393-telerik-kendo-ui-feedback/suggestions/8987827-responsive-design-for-the-pivotgrid
The PivotGrid is responsive, but as a complex widget the developer needs to re-size it accordingly.
With regards to the used media query, we decided to limit the screen size, as the purpose of the widget is display a lot of data and it will not be very usable on mobile device. Nevertheless, if you want to use it mobile device, you can freely do that.
Regards,
Georgi Krustev
Telerik

I made it as responsive as possible: http://dojo.telerik.com/idaxE
That's not too bad. But still i see room for improvement.
Eventually some improvements can be made by including this feature:
Forum: http://www.telerik.com/forums/resizing-the-width-of-fields
Feature Request: http://kendoui-feedback.telerik.com/forums/127393-telerik-kendo-ui-feedback/suggestions/8987869-resizing-the-width-of-fields-of-the-pivotgrid
In the meantime i understood what you meant by "The PivotGrid is responsive, but as a complex widget the developer needs to re-size it accordingly." and you are right. The PivotGrid is quite responsive, especially compared two your competitors solutions.
The only problem i see regarding the pivot grid is the static column width. Therefor i rewrote my feature request for more details and clarity and deleted the old one.