Accessing Parent List Content in host web using ListData.svc from SharePoint App

I have a SharePoint App which needs to load the contents of a list in the host web.  I am using ListData.svc and the following code.

    var listUrl = https://jspsite/sites/MyDevSite/_vti_bin/ListData.svc/EventCal1
    try {
        $.getJSON(listUrl, function (data) {
            alert("Pre result.");
            for (var i = 0; i < data.d.results.length; i++) {
                alert("Result");
            }
        });
    } catch (e) {
        alert("Error");
    }