protected override void OnStart()
        {
            string iKey = null;

            Device.OnPlatform(
                Android: () => {
                iKey = "<YOUR-IOS-KEY>";
            },
                iOS: () => {
                iKey = "<YOUR-ANDROID-KEY>";
            }
                );
            ApplicationInsights.Setup(iKey);
            ApplicationInsights.SetDebugLogEnabled(true);
            // Set up common properties
            Dictionary <string, string> commonProperties = new Dictionary <string, string> ();

            commonProperties.Add("Common Key", "Common Property Value");
            ApplicationInsights.SetCommonProperties(commonProperties);
            ApplicationInsights.Start();
        }