angularjs date filter not formatting my json value

As mentioned in the comments by charlietfl, a clean option would be to update the service to return a date format already compatible with the built-in angular filters.

However, if this is not possible, you could set up a custom filter to parse your dates.

A (very small) library that I recommend is Moment.js: http://momentjs.com/

The following is an example blog post on how to wrap Moment.js in a custom angular filter: http://www.34m0.com/2012/07/angularjs-user-friendly-date-display.html

angular.module('myModule').
    filter('fromNow', function() {
        return function(dateString) {
            return moment(new Date(dateString)).fromNow()
        };
    });

This would be used like:

{{ reply.createdDate | fromNow }}

You can place this in your controller:

  $scope.toJsDate = function(str){
    if(!str)return null;
    return new Date(str);
  }

and then:

{{toJsDate(values.SomeDate)| date:'mediumTime' }}

I would second @AlexOsborn's suggestion to use moment.js to create a custom filter because moment.js can parse the string containing the date. In my implementation of the filter, I also delegate date formatting to moment.js because I feel moment.js' date formatting feature is more comprehensive than angular.js':

angular
.module("YourModuleNameHere")
.filter("formatdate", [function () {
    var result = function (date, formatstring) {
        if(formatstring === null) {
            formatstring = "DD MMM YYYY";
        }
        return moment(date).format(formatstring);
    }
    return result;
}]);

And you use it just like you'd use angular.js date filter (but to format the date you'd use moment.js formatting codes):

<p>Today is {{moment() | formatdate}}</p>
<p>Another date: {{values.SomeDate | formatdate:"ddd D MMM YYYY"}}</p>