Note: I've inspired from inAppPurchase Cordova Plugin's test example code. This is my service file for Ionic Framework with In App Purchase plugin for Cordova:
(function() {
angular.module('trackFollowersApp').service('inAppPurchase', function($resource) {
var IAP = {
initialize: function() {
if (!window.storekit) {
console.log('In-App Purchases not available');