Kendo UI loop through collection in Json within template for ListView

You can have arbitrary JavaScript code inside a template:

<script type="text/x-kendo-tmpl" id="template">
    <div class="subscriberFunction">
        <h3>${Title}</h3>
       <!-- Display KeyPairs -->
         <ul>
         # for (var key in KeyPairs) { #
              <li>${ KeyPairs[key] }</li>
         # } #
         </ul>
    </div>
</script>

You can do this with a counter in the for-loop. This should fix your issue:

<script type="text/x-kendo-tmpl" id="template">
    <div class="subscriberFunction">
        <h3>${Title}</h3>
        <!-- Display KeyPairs -->
        <ul>
            #for (var i=0,len=KeyPairs.length; i<len; i++){#
                <li>${ KeyPairs[i] }</li>
            # } #
        </ul>
    </div>
</script>