I posted my reply in the support ticket on the same topic. For convenience I am pasting it below:
The service will convert the result to JSON so the result will be wrapped twice. You should leave the service to serialize the data and return just a collection of objects in order to avoid the problem. We do not have examples specifically for Kendo Mobile that use page methods but I can suggest to check the ASP examples from our GitHub repository which can be found on this page. The examples use a Web Grid but the dataSource is the same so you can use the same approach.
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