So far we have not tested Kendo UI on Google App Engine. According to the description here it supports Java and PHP languages, therefore in theory you should be able to build and deploy apps created with Telerik UI for JSP and Telerik UI for PHP (products powered internally by Kendo UI) on this engine.
Let us know if you experience any particular issues related to our products when building such applications.
Regards,
Sebastian
Telerik
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