diff --git a/ChangeLog.txt b/ChangeLog.txt
index d0ff092ef..644a79a4e 100644
--- a/ChangeLog.txt
+++ b/ChangeLog.txt
@@ -1,5 +1,15 @@
 Google Mobile Ads Unity Plugin Change Log
 
+*************
+Version 3.1.2
+*************
+- Fix NPE when ad events are not hooked up.
+
+Built and tested with:
+- Google Play services 9.8.0
+- Google Mobile Ads iOS SDK 7.13.0
+- Unity Jar Resolver 1.2.2.0
+
 *************
 Version 3.1.1
 *************
diff --git a/source/plugin/Assets/GoogleMobileAds/Api/AdLoader.cs b/source/plugin/Assets/GoogleMobileAds/Api/AdLoader.cs
index 7f90ad29c..edeb0c67d 100644
--- a/source/plugin/Assets/GoogleMobileAds/Api/AdLoader.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Api/AdLoader.cs
@@ -39,16 +39,21 @@ private AdLoader(Builder builder)
             this.AdTypes = new HashSet<NativeAdType>(builder.AdTypes);
             this.adLoaderClient = GoogleMobileAdsClientFactory.BuildAdLoaderClient(this);
 
-            this.adLoaderClient.OnCustomNativeTemplateAdLoaded +=
-                    delegate(object sender, CustomNativeEventArgs args)
-            {
-                this.OnCustomNativeTemplateAdLoaded(this, args);
-            };
-            this.adLoaderClient.OnAdFailedToLoad += delegate(
-                object sender, AdFailedToLoadEventArgs args)
-            {
-                this.OnAdFailedToLoad(this, args);
-            };
+            this.adLoaderClient.OnCustomNativeTemplateAdLoaded += (sender, args) =>
+                {
+                    if(this.OnCustomNativeTemplateAdLoaded != null)
+                    {
+                        this.OnCustomNativeTemplateAdLoaded(this, args);
+                    }
+                };
+
+            this.adLoaderClient.OnAdFailedToLoad += (sender, args) =>
+                {
+                    if(this.OnAdFailedToLoad != null)
+                    {
+                        this.OnAdFailedToLoad(this, args);
+                    }
+                };
         }
 
         public event EventHandler<AdFailedToLoadEventArgs> OnAdFailedToLoad;
diff --git a/source/plugin/Assets/GoogleMobileAds/Api/AdLoader.cs.meta b/source/plugin/Assets/GoogleMobileAds/Api/AdLoader.cs.meta
new file mode 100644
index 000000000..c5ea30758
--- /dev/null
+++ b/source/plugin/Assets/GoogleMobileAds/Api/AdLoader.cs.meta
@@ -0,0 +1,12 @@
+fileFormatVersion: 2
+guid: f5474196001554b6da135319d9475e61
+timeCreated: 1477084497
+licenseType: Free
+MonoImporter:
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/source/plugin/Assets/GoogleMobileAds/Api/AdRequest.cs b/source/plugin/Assets/GoogleMobileAds/Api/AdRequest.cs
index 330b8d008..20fa4dcf7 100644
--- a/source/plugin/Assets/GoogleMobileAds/Api/AdRequest.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Api/AdRequest.cs
@@ -20,7 +20,7 @@ namespace GoogleMobileAds.Api
 {
     public class AdRequest
     {
-        public const string Version = "3.1.1";
+        public const string Version = "3.1.2";
         public const string TestDeviceSimulator = "SIMULATOR";
 
         public class Builder
diff --git a/source/plugin/Assets/GoogleMobileAds/Api/BannerView.cs b/source/plugin/Assets/GoogleMobileAds/Api/BannerView.cs
index b25fe336b..373b20c3c 100644
--- a/source/plugin/Assets/GoogleMobileAds/Api/BannerView.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Api/BannerView.cs
@@ -23,11 +23,11 @@ public class BannerView
         private IBannerClient client;
 
         // These are the ad callback events that can be hooked into.
-        public event EventHandler<EventArgs> OnAdLoaded = delegate {};
-        public event EventHandler<AdFailedToLoadEventArgs> OnAdFailedToLoad = delegate {};
-        public event EventHandler<EventArgs> OnAdOpening = delegate {};
-        public event EventHandler<EventArgs> OnAdClosed = delegate {};
-        public event EventHandler<EventArgs> OnAdLeavingApplication = delegate {};
+        public event EventHandler<EventArgs> OnAdLoaded;
+        public event EventHandler<AdFailedToLoadEventArgs> OnAdFailedToLoad;
+        public event EventHandler<EventArgs> OnAdOpening;
+        public event EventHandler<EventArgs> OnAdClosed;
+        public event EventHandler<EventArgs> OnAdLeavingApplication;
 
         // Creates a BannerView and adds it to the view hierarchy.
         public BannerView(string adUnitId, AdSize adSize, AdPosition position)
@@ -35,30 +35,45 @@ public BannerView(string adUnitId, AdSize adSize, AdPosition position)
             client = GoogleMobileAdsClientFactory.BuildBannerClient();
             client.CreateBannerView(adUnitId, adSize, position);
 
-            client.OnAdLoaded += delegate(object sender, EventArgs args)
-            {
-                OnAdLoaded(this, args);
-            };
+            this.client.OnAdLoaded += (sender, args) =>
+                {
+                    if(this.OnAdLoaded != null)
+                    {
+                        this.OnAdLoaded(this, args);
+                    }
+                };
 
-            client.OnAdFailedToLoad += delegate(object sender, AdFailedToLoadEventArgs args)
-            {
-                OnAdFailedToLoad(this, args);
-            };
+            this.client.OnAdFailedToLoad += (sender, args) =>
+                {
+                    if(this.OnAdLoaded != null)
+                    {
+                        this.OnAdLoaded(this, args);
+                    }
+                };
 
-            client.OnAdOpening += delegate(object sender, EventArgs args)
-            {
-                OnAdOpening(this, args);
-            };
+            this.client.OnAdOpening += (sender, args) =>
+                {
+                    if(this.OnAdOpening != null)
+                    {
+                        this.OnAdOpening(this, args);
+                    }
+                };
 
-            client.OnAdClosed += delegate(object sender, EventArgs args)
-            {
-                OnAdClosed(this, args);
-            };
+            this.client.OnAdClosed += (sender, args) =>
+                {
+                    if(this.OnAdClosed != null)
+                    {
+                        this.OnAdClosed(this, args);
+                    }
+                };
 
-            client.OnAdLeavingApplication += delegate(object sender, EventArgs args)
-            {
-                OnAdLeavingApplication(this, args);
-            };
+            this.client.OnAdLeavingApplication += (sender, args) =>
+                {
+                    if(this.OnAdLeavingApplication != null)
+                    {
+                        this.OnAdLeavingApplication(this, args);
+                    }
+                };
         }
 
         // Loads an ad into the BannerView.
diff --git a/source/plugin/Assets/GoogleMobileAds/Api/CustomNativeEventArgs.cs.meta b/source/plugin/Assets/GoogleMobileAds/Api/CustomNativeEventArgs.cs.meta
new file mode 100644
index 000000000..7b9cb1b49
--- /dev/null
+++ b/source/plugin/Assets/GoogleMobileAds/Api/CustomNativeEventArgs.cs.meta
@@ -0,0 +1,12 @@
+fileFormatVersion: 2
+guid: 5188b1fa1a1b148ce8e88835595e660d
+timeCreated: 1477084497
+licenseType: Free
+MonoImporter:
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/source/plugin/Assets/GoogleMobileAds/Api/CustomNativeTemplateAd.cs.meta b/source/plugin/Assets/GoogleMobileAds/Api/CustomNativeTemplateAd.cs.meta
new file mode 100644
index 000000000..30e8c0e49
--- /dev/null
+++ b/source/plugin/Assets/GoogleMobileAds/Api/CustomNativeTemplateAd.cs.meta
@@ -0,0 +1,12 @@
+fileFormatVersion: 2
+guid: 6f029b4086c1141ffad2e59dd23f14f4
+timeCreated: 1477084497
+licenseType: Free
+MonoImporter:
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/source/plugin/Assets/GoogleMobileAds/Api/InterstitialAd.cs b/source/plugin/Assets/GoogleMobileAds/Api/InterstitialAd.cs
index 8c7b6792f..b783e6355 100644
--- a/source/plugin/Assets/GoogleMobileAds/Api/InterstitialAd.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Api/InterstitialAd.cs
@@ -34,30 +34,45 @@ public InterstitialAd(string adUnitId)
             client = GoogleMobileAdsClientFactory.BuildInterstitialClient();
             client.CreateInterstitialAd(adUnitId);
 
-            client.OnAdLoaded += delegate(object sender, EventArgs args)
-            {
-                OnAdLoaded(this, args);
-            };
+            this.client.OnAdLoaded += (sender, args) =>
+                {
+                    if(this.OnAdLoaded != null)
+                    {
+                        this.OnAdLoaded(this, args);
+                    }
+                };
 
-            client.OnAdFailedToLoad += delegate(object sender, AdFailedToLoadEventArgs args)
-            {
-                OnAdFailedToLoad(this, args);
-            };
+            this.client.OnAdFailedToLoad += (sender, args) =>
+                {
+                    if(this.OnAdLoaded != null)
+                    {
+                        this.OnAdLoaded(this, args);
+                    }
+                };
 
-            client.OnAdOpening += delegate(object sender, EventArgs args)
-            {
-                OnAdOpening(this, args);
-            };
+            this.client.OnAdOpening += (sender, args) =>
+                {
+                    if(this.OnAdOpening != null)
+                    {
+                        this.OnAdOpening(this, args);
+                    }
+                };
 
-            client.OnAdClosed += delegate(object sender, EventArgs args)
-            {
-                OnAdClosed(this, args);
-            };
+            this.client.OnAdClosed += (sender, args) =>
+                {
+                    if(this.OnAdClosed != null)
+                    {
+                        this.OnAdClosed(this, args);
+                    }
+                };
 
-            client.OnAdLeavingApplication += delegate(object sender, EventArgs args)
-            {
-                OnAdLeavingApplication(this, args);
-            };
+            this.client.OnAdLeavingApplication += (sender, args) =>
+                {
+                    if(this.OnAdLeavingApplication != null)
+                    {
+                        this.OnAdLeavingApplication(this, args);
+                    }
+                };
         }
 
         // Loads an InterstitialAd.
diff --git a/source/plugin/Assets/GoogleMobileAds/Api/NativeExpressAdView.cs b/source/plugin/Assets/GoogleMobileAds/Api/NativeExpressAdView.cs
index bc6ac2a2d..64c22ceee 100644
--- a/source/plugin/Assets/GoogleMobileAds/Api/NativeExpressAdView.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Api/NativeExpressAdView.cs
@@ -28,16 +28,45 @@ public NativeExpressAdView(string adUnitId, AdSize adSize, AdPosition position)
             this.client = GoogleMobileAdsClientFactory.BuildNativeExpressAdClient();
             this.client.CreateNativeExpressAdView(adUnitId, adSize, position);
 
-            this.client.OnAdLoaded += (sender, args) => this.OnAdLoaded(this, args);
-
-            this.client.OnAdFailedToLoad += (sender, args) => this.OnAdFailedToLoad(this, args);
-
-            this.client.OnAdOpening += (sender, args) => this.OnAdOpening(this, args);
-
-            this.client.OnAdClosed += (sender, args) => this.OnAdClosed(this, args);
+            this.client.OnAdLoaded += (sender, args) =>
+                {
+                    if(this.OnAdLoaded != null)
+                    {
+                         this.OnAdLoaded(this, args);
+                    }
+                };
+
+            this.client.OnAdFailedToLoad += (sender, args) =>
+                {
+                    if(this.OnAdLoaded != null)
+                    {
+                        this.OnAdLoaded(this, args);
+                    }
+                };
+
+            this.client.OnAdOpening += (sender, args) =>
+                {
+                    if(this.OnAdOpening != null)
+                    {
+                        this.OnAdOpening(this, args);
+                    }
+                };
+
+            this.client.OnAdClosed += (sender, args) =>
+                {
+                    if(this.OnAdClosed != null)
+                    {
+                        this.OnAdClosed(this, args);
+                    }
+                };
 
             this.client.OnAdLeavingApplication += (sender, args) =>
-                this.OnAdLeavingApplication(this, args);
+                {
+                    if(this.OnAdLeavingApplication != null)
+                    {
+                        this.OnAdLeavingApplication(this, args);
+                    }
+                };
         }
 
         // These are the ad callback events that can be hooked into.
diff --git a/source/plugin/Assets/GoogleMobileAds/Api/RewardBasedVideoAd.cs b/source/plugin/Assets/GoogleMobileAds/Api/RewardBasedVideoAd.cs
index ba4f3f987..f9f8b7290 100644
--- a/source/plugin/Assets/GoogleMobileAds/Api/RewardBasedVideoAd.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Api/RewardBasedVideoAd.cs
@@ -50,40 +50,61 @@ private RewardBasedVideoAd()
             client = GoogleMobileAdsClientFactory.BuildRewardBasedVideoAdClient();
             client.CreateRewardBasedVideoAd();
 
-            client.OnAdLoaded += delegate(object sender, EventArgs args)
-            {
-                OnAdLoaded(this, args);
-            };
+            this.client.OnAdLoaded += (sender, args) =>
+                {
+                    if (this.OnAdLoaded != null)
+                    {
+                        this.OnAdLoaded(this, args);
+                    }
+                };
 
-            client.OnAdFailedToLoad += delegate(object sender, AdFailedToLoadEventArgs args)
-            {
-                OnAdFailedToLoad(this, args);
-            };
+            this.client.OnAdFailedToLoad += (sender, args) =>
+                {
+                    if (this.OnAdLoaded != null)
+                    {
+                        this.OnAdLoaded(this, args);
+                    }
+                };
 
-            client.OnAdOpening += delegate(object sender, EventArgs args)
-            {
-                OnAdOpening(this, args);
-            };
+            this.client.OnAdOpening += (sender, args) =>
+                {
+                    if (this.OnAdOpening != null)
+                    {
+                        this.OnAdOpening(this, args);
+                    }
+                };
 
-            client.OnAdStarted += delegate(object sender, EventArgs args)
-            {
-                OnAdStarted(this, args);
-            };
+            this.client.OnAdStarted += (sender, args) =>
+                {
+                    if (this.OnAdStarted != null)
+                    {
+                        this.OnAdStarted(this, args);
+                    }
+                };
 
-            client.OnAdRewarded += delegate(object sender, Reward args)
-            {
-                OnAdRewarded(this, args);
-            };
+            this.client.OnAdClosed += (sender, args) =>
+                {
+                    if (this.OnAdClosed != null)
+                    {
+                        this.OnAdClosed(this, args);
+                    }
+                };
 
-            client.OnAdClosed += delegate(object sender, EventArgs args)
-            {
-                OnAdClosed(this, args);
-            };
+            this.client.OnAdLeavingApplication += (sender, args) =>
+                {
+                    if (this.OnAdLeavingApplication != null)
+                    {
+                        this.OnAdLeavingApplication(this, args);
+                    }
+                };
 
-            client.OnAdLeavingApplication += delegate(object sender, EventArgs args)
-            {
-                OnAdLeavingApplication(this, args);
-            };
+            this.client.OnAdRewarded += (sender, args) =>
+                {
+                    if (this.OnAdRewarded != null)
+                    {
+                        this.OnAdRewarded(this, args);
+                    }
+                };
         }
 
         // Loads a new reward based video ad request
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/Android/AdLoaderClient.cs b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/AdLoaderClient.cs
index 3cd6667c7..2ba8f2d34 100644
--- a/source/plugin/Assets/GoogleMobileAds/Platforms/Android/AdLoaderClient.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/AdLoaderClient.cs
@@ -59,18 +59,25 @@ public void LoadAd(AdRequest request)
 
         public void onCustomTemplateAdLoaded(AndroidJavaObject ad)
         {
-            CustomNativeEventArgs args = new CustomNativeEventArgs() {
-                nativeAd = new CustomNativeTemplateAd(new CustomNativeTemplateClient(ad))
-            };
-            OnCustomNativeTemplateAdLoaded(this, args);
+            if (this.OnCustomNativeTemplateAdLoaded != null)
+            {
+                CustomNativeEventArgs args = new CustomNativeEventArgs() {
+                    nativeAd = new CustomNativeTemplateAd(new CustomNativeTemplateClient(ad))
+                };
+                this.OnCustomNativeTemplateAdLoaded(this, args);
+            }
         }
 
         void onAdFailedToLoad(string errorReason)
         {
-            AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs() {
-                Message = errorReason
-            };
-            OnAdFailedToLoad(this, args);
+            if (this.OnAdFailedToLoad != null)
+            {
+                AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+                {
+                    Message = errorReason
+                };
+                this.OnAdFailedToLoad(this, args);
+            }
         }
 
         public void onCustomClick(AndroidJavaObject ad, string assetName)
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/Android/AdLoaderClient.cs.meta b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/AdLoaderClient.cs.meta
new file mode 100644
index 000000000..26de1aa99
--- /dev/null
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/AdLoaderClient.cs.meta
@@ -0,0 +1,12 @@
+fileFormatVersion: 2
+guid: 5bc0a5f7f000d4027bd3e5192cc1269a
+timeCreated: 1477084497
+licenseType: Free
+MonoImporter:
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/Android/BannerClient.cs b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/BannerClient.cs
index ff025c448..b26c1ccc6 100644
--- a/source/plugin/Assets/GoogleMobileAds/Platforms/Android/BannerClient.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/BannerClient.cs
@@ -82,31 +82,46 @@ public void DestroyBannerView()
 
         public void onAdLoaded()
         {
-            this.OnAdLoaded(this, EventArgs.Empty);
+            if (this.OnAdLoaded != null)
+            {
+                this.OnAdLoaded(this, EventArgs.Empty);
+            }
         }
 
         public void onAdFailedToLoad(string errorReason)
         {
-            AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+            if (this.OnAdFailedToLoad != null)
             {
-                Message = errorReason
-            };
-            this.OnAdFailedToLoad(this, args);
+                AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+                {
+                    Message = errorReason
+                };
+                this.OnAdFailedToLoad(this, args);
+            }
         }
 
         public void onAdOpened()
         {
-            this.OnAdOpening(this, EventArgs.Empty);
+            if (this.OnAdOpening != null)
+            {
+                this.OnAdOpening(this, EventArgs.Empty);
+            }
         }
 
         public void onAdClosed()
         {
-            this.OnAdClosed(this, EventArgs.Empty);
+            if (this.OnAdClosed != null)
+            {
+                this.OnAdClosed(this, EventArgs.Empty);
+            }
         }
 
         public void onAdLeftApplication()
         {
-            this.OnAdLeavingApplication(this, EventArgs.Empty);
+            if (this.OnAdLeavingApplication != null)
+            {
+                this.OnAdLeavingApplication(this, EventArgs.Empty);
+            }
         }
 
         #endregion
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/Android/CustomNativeTemplateClient.cs.meta b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/CustomNativeTemplateClient.cs.meta
new file mode 100644
index 000000000..1e3794ea1
--- /dev/null
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/CustomNativeTemplateClient.cs.meta
@@ -0,0 +1,12 @@
+fileFormatVersion: 2
+guid: 7e76e9223a0d64aa7972f18446dab8ff
+timeCreated: 1477084497
+licenseType: Free
+MonoImporter:
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/Android/InterstitialClient.cs b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/InterstitialClient.cs
index dcfb8941c..fa678dd77 100644
--- a/source/plugin/Assets/GoogleMobileAds/Platforms/Android/InterstitialClient.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/InterstitialClient.cs
@@ -98,31 +98,46 @@ public void SetCustomInAppPurchaseProcessor(ICustomInAppPurchaseProcessor proces
 
         public void onAdLoaded()
         {
-            this.OnAdLoaded(this, EventArgs.Empty);
+            if (this.OnAdLoaded != null)
+            {
+                this.OnAdLoaded(this, EventArgs.Empty);
+            }
         }
 
         public void onAdFailedToLoad(string errorReason)
         {
-            AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+            if (this.OnAdFailedToLoad != null)
             {
-                Message = errorReason
-            };
-            this.OnAdFailedToLoad(this, args);
+                AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+                {
+                    Message = errorReason
+                };
+                this.OnAdFailedToLoad(this, args);
+            }
         }
 
         public void onAdOpened()
         {
-            this.OnAdOpening(this, EventArgs.Empty);
+            if (this.OnAdOpening != null)
+            {
+                this.OnAdOpening(this, EventArgs.Empty);
+            }
         }
 
         public void onAdClosed()
         {
-            this.OnAdClosed(this, EventArgs.Empty);
+            if (this.OnAdClosed != null)
+            {
+                this.OnAdClosed(this, EventArgs.Empty);
+            }
         }
 
         public void onAdLeftApplication()
         {
-            this.OnAdLeavingApplication(this, EventArgs.Empty);
+            if (this.OnAdLeavingApplication != null)
+            {
+                this.OnAdLeavingApplication(this, EventArgs.Empty);
+            }
         }
 
         #endregion
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/Android/NativeExpressAdClient.cs b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/NativeExpressAdClient.cs
index ab26604e4..1bd75c23d 100644
--- a/source/plugin/Assets/GoogleMobileAds/Platforms/Android/NativeExpressAdClient.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/NativeExpressAdClient.cs
@@ -88,31 +88,46 @@ public void DestroyNativeExpressAdView()
 
         public void onAdLoaded()
         {
-            this.OnAdLoaded(this, EventArgs.Empty);
+            if (this.OnAdLoaded != null)
+            {
+                this.OnAdLoaded(this, EventArgs.Empty);
+            }
         }
 
         public void onAdFailedToLoad(string errorReason)
         {
-            AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+            if (this.OnAdFailedToLoad != null)
             {
-                Message = errorReason
-            };
-            this.OnAdFailedToLoad(this, args);
+                AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+                {
+                    Message = errorReason
+                };
+                this.OnAdFailedToLoad(this, args);
+            }
         }
 
         public void onAdOpened()
         {
-            this.OnAdOpening(this, EventArgs.Empty);
+            if (this.OnAdOpening != null)
+            {
+                this.OnAdOpening(this, EventArgs.Empty);
+            }
         }
 
         public void onAdClosed()
         {
-            this.OnAdClosed(this, EventArgs.Empty);
+            if (this.OnAdClosed != null)
+            {
+                this.OnAdClosed(this, EventArgs.Empty);
+            }
         }
 
         public void onAdLeftApplication()
         {
-            this.OnAdLeavingApplication(this, EventArgs.Empty);
+            if (this.OnAdLeavingApplication != null)
+            {
+                this.OnAdLeavingApplication(this, EventArgs.Empty);
+            }
         }
 
         #endregion
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/Android/RewardBasedVideoAdClient.cs b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/RewardBasedVideoAdClient.cs
index 9da9ca561..55f8c6f5d 100644
--- a/source/plugin/Assets/GoogleMobileAds/Platforms/Android/RewardBasedVideoAdClient.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/Android/RewardBasedVideoAdClient.cs
@@ -73,44 +73,66 @@ public void DestroyRewardBasedVideoAd() {
 
         void onAdLoaded()
         {
-            OnAdLoaded(this, EventArgs.Empty);
+            if (this.OnAdLoaded != null)
+            {
+                this.OnAdLoaded(this, EventArgs.Empty);
+            }
         }
 
         void onAdFailedToLoad(string errorReason)
         {
-            AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs() {
-                Message = errorReason
-            };
-            OnAdFailedToLoad(this, args);
+            if (this.OnAdFailedToLoad != null)
+            {
+                AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+                {
+                    Message = errorReason
+                };
+                this.OnAdFailedToLoad(this, args);
+            }
         }
 
         void onAdOpened()
         {
-            OnAdOpening(this , EventArgs.Empty);
+            if (this.OnAdOpening != null)
+            {
+                this.OnAdOpening(this, EventArgs.Empty);
+            }
         }
 
         void onAdStarted()
         {
-            OnAdStarted(this, EventArgs.Empty);
+            if (this.OnAdStarted != null)
+            {
+                this.OnAdStarted(this, EventArgs.Empty);
+            }
         }
 
         void onAdClosed()
         {
-            OnAdClosed(this, EventArgs.Empty);
+            if (this.OnAdClosed != null)
+            {
+                this.OnAdClosed(this, EventArgs.Empty);
+            }
         }
 
         void onAdRewarded(string type, float amount)
         {
-            Reward args = new Reward() {
-                Type = type,
-                Amount = amount
-            };
-            OnAdRewarded(this, args);
+            if (this.OnAdRewarded != null)
+            {
+                Reward args = new Reward() {
+                    Type = type,
+                    Amount = amount
+                };
+                this.OnAdRewarded(this, args);
+            }
         }
 
         void onAdLeftApplication()
         {
-            OnAdLeavingApplication(this, EventArgs.Empty);
+            if (this.OnAdLeavingApplication != null)
+            {
+                this.OnAdLeavingApplication(this, EventArgs.Empty);
+            }
         }
 
         #endregion
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/AdLoaderClient.cs b/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/AdLoaderClient.cs
index c5e8bf9f2..afeefb61f 100644
--- a/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/AdLoaderClient.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/AdLoaderClient.cs
@@ -124,12 +124,16 @@ private static void AdLoaderDidReceiveNativeCustomTemplateAdCallback(
                     client.customNativeTemplateCallbacks.ContainsKey(templateID) ?
                     client.customNativeTemplateCallbacks[templateID] : null;
 
-            CustomNativeEventArgs args = new CustomNativeEventArgs()
+            if (client.OnCustomNativeTemplateAdLoaded != null)
             {
-                nativeAd = new CustomNativeTemplateAd(new CustomNativeTemplateClient(
-                    nativeCustomTemplateAd, clickHandler))
-            };
-            client.OnCustomNativeTemplateAdLoaded(client, args);
+                CustomNativeEventArgs args = new CustomNativeEventArgs()
+                {
+                    nativeAd = new CustomNativeTemplateAd(new CustomNativeTemplateClient(
+                        nativeCustomTemplateAd, clickHandler))
+                };
+                client.OnCustomNativeTemplateAdLoaded(client, args);
+            }
+
         }
 
         [MonoPInvokeCallback(typeof(GADUAdLoaderDidFailToReceiveAdWithErrorCallback))]
@@ -137,11 +141,14 @@ private static void AdLoaderDidFailToReceiveAdWithErrorCallback(
             IntPtr adLoader, string error)
         {
             AdLoaderClient client = IntPtrToAdLoaderClient(adLoader);
-            AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+            if (client.OnAdFailedToLoad != null)
             {
-                Message = error
-            };
-            client.OnAdFailedToLoad(client, args);
+                AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+                {
+                    Message = error
+                };
+                client.OnAdFailedToLoad(client, args);
+            }
         }
 
         private static AdLoaderClient IntPtrToAdLoaderClient(IntPtr adLoader)
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/BannerClient.cs b/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/BannerClient.cs
index 506e81c14..7076a2c4e 100644
--- a/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/BannerClient.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/BannerClient.cs
@@ -142,7 +142,10 @@ public void Dispose()
         private static void AdViewDidReceiveAdCallback(IntPtr bannerClient)
         {
             BannerClient client = IntPtrToBannerClient(bannerClient);
-            client.OnAdLoaded(client, EventArgs.Empty);
+            if (client.OnAdLoaded != null)
+            {
+                client.OnAdLoaded(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADUAdViewDidFailToReceiveAdWithErrorCallback))]
@@ -150,32 +153,44 @@ private static void AdViewDidFailToReceiveAdWithErrorCallback(
                 IntPtr bannerClient, string error)
         {
             BannerClient client = IntPtrToBannerClient(bannerClient);
-            AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+            if (client.OnAdFailedToLoad != null)
             {
-                Message = error
-            };
-            client.OnAdFailedToLoad(client, args);
+                AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+                {
+                    Message = error
+                };
+                client.OnAdFailedToLoad(client, args);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADUAdViewWillPresentScreenCallback))]
         private static void AdViewWillPresentScreenCallback(IntPtr bannerClient)
         {
             BannerClient client = IntPtrToBannerClient(bannerClient);
-            client.OnAdOpening(client, EventArgs.Empty);
+            if (client.OnAdOpening != null)
+            {
+                client.OnAdOpening(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADUAdViewDidDismissScreenCallback))]
         private static void AdViewDidDismissScreenCallback(IntPtr bannerClient)
         {
             BannerClient client = IntPtrToBannerClient(bannerClient);
-            client.OnAdClosed(client, EventArgs.Empty);
+            if (client.OnAdClosed != null)
+            {
+                client.OnAdClosed(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADUAdViewWillLeaveApplicationCallback))]
         private static void AdViewWillLeaveApplicationCallback(IntPtr bannerClient)
         {
             BannerClient client = IntPtrToBannerClient(bannerClient);
-            client.OnAdLeavingApplication(client, EventArgs.Empty);
+            if (client.OnAdLeavingApplication != null)
+            {
+                client.OnAdLeavingApplication(client, EventArgs.Empty);
+            }
         }
 
         private static BannerClient IntPtrToBannerClient(IntPtr bannerClient)
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/CustomNativeTemplateClient.cs b/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/CustomNativeTemplateClient.cs
index 0e78863bf..cd08e7708 100644
--- a/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/CustomNativeTemplateClient.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/CustomNativeTemplateClient.cs
@@ -142,8 +142,12 @@ private static void NativeCustomTemplateDidReceiveClickCallback(
             IntPtr nativeCustomAd, string assetName)
         {
             CustomNativeTemplateClient client = IntPtrToAdLoaderClient(nativeCustomAd);
-            CustomNativeTemplateAd nativeAd = new CustomNativeTemplateAd(client);
-            client.clickHandler(nativeAd, assetName);
+            if (client.clickHandler != null)
+            {
+                CustomNativeTemplateAd nativeAd = new CustomNativeTemplateAd(client);
+                client.clickHandler(nativeAd, assetName);
+            }
+
         }
 
         private static CustomNativeTemplateClient IntPtrToAdLoaderClient(
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/InterstitialClient.cs b/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/InterstitialClient.cs
index 85e3fd9ca..ff27a588a 100644
--- a/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/InterstitialClient.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/InterstitialClient.cs
@@ -143,7 +143,10 @@ public void SetCustomInAppPurchaseProcessor(ICustomInAppPurchaseProcessor proces
         private static void InterstitialDidReceiveAdCallback(IntPtr interstitialClient)
         {
             InterstitialClient client = IntPtrToInterstitialClient(interstitialClient);
-            client.OnAdLoaded(client, EventArgs.Empty);
+            if (client.OnAdLoaded != null)
+            {
+                client.OnAdLoaded(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADUInterstitialDidFailToReceiveAdWithErrorCallback))]
@@ -151,32 +154,44 @@ private static void InterstitialDidFailToReceiveAdWithErrorCallback(
                 IntPtr interstitialClient, string error)
         {
             InterstitialClient client = IntPtrToInterstitialClient(interstitialClient);
-            AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+            if (client.OnAdFailedToLoad != null)
             {
-                Message = error
-            };
-            client.OnAdFailedToLoad(client, args);
+                AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+                {
+                    Message = error
+                };
+                client.OnAdFailedToLoad(client, args);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADUInterstitialWillPresentScreenCallback))]
         private static void InterstitialWillPresentScreenCallback(IntPtr interstitialClient)
         {
             InterstitialClient client = IntPtrToInterstitialClient(interstitialClient);
-            client.OnAdOpening(client, EventArgs.Empty);
+            if (client.OnAdOpening != null)
+            {
+                client.OnAdOpening(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADUInterstitialDidDismissScreenCallback))]
         private static void InterstitialDidDismissScreenCallback(IntPtr interstitialClient)
         {
             InterstitialClient client = IntPtrToInterstitialClient(interstitialClient);
-            client.OnAdClosed(client, EventArgs.Empty);
+            if (client.OnAdClosed != null)
+            {
+                client.OnAdClosed(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADUInterstitialWillLeaveApplicationCallback))]
         private static void InterstitialWillLeaveApplicationCallback(IntPtr interstitialClient)
         {
             InterstitialClient client = IntPtrToInterstitialClient(interstitialClient);
-            client.OnAdLeavingApplication(client, EventArgs.Empty);
+            if (client.OnAdLeavingApplication != null)
+            {
+                client.OnAdLeavingApplication(client, EventArgs.Empty);
+            }
         }
 
         private static InterstitialClient IntPtrToInterstitialClient(IntPtr interstitialClient)
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/NativeExpressAdClient.cs b/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/NativeExpressAdClient.cs
index 2094e0a44..a82e5845c 100644
--- a/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/NativeExpressAdClient.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/NativeExpressAdClient.cs
@@ -132,7 +132,10 @@ public void Dispose()
         private static void NativeExpressAdViewDidReceiveAdCallback(IntPtr nativeExpressClient)
         {
             NativeExpressAdClient client = IntPtrToNativeExpressAdClient(nativeExpressClient);
-            client.OnAdLoaded(client, EventArgs.Empty);
+            if(client.OnAdLoaded != null)
+            {
+                client.OnAdLoaded(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADUNativeExpressAdViewDidFailToReceiveAdWithErrorCallback))]
@@ -140,32 +143,44 @@ private static void NativeExpressAdViewDidFailToReceiveAdWithErrorCallback(
             IntPtr nativeExpressClient, string error)
         {
             NativeExpressAdClient client = IntPtrToNativeExpressAdClient(nativeExpressClient);
-            AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+            if(client.OnAdFailedToLoad != null)
             {
-                Message = error
-            };
-            client.OnAdFailedToLoad(client, args);
+                AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+                {
+                    Message = error
+                };
+                client.OnAdFailedToLoad(client, args);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADUNativeExpressAdViewWillPresentScreenCallback))]
         private static void NativeExpressAdViewWillPresentScreenCallback(IntPtr nativeExpressClient)
         {
             NativeExpressAdClient client = IntPtrToNativeExpressAdClient(nativeExpressClient);
-            client.OnAdOpening(client, EventArgs.Empty);
+            if(client.OnAdOpening != null)
+            {
+                client.OnAdOpening(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADUNativeExpressAdViewDidDismissScreenCallback))]
         private static void NativeExpressAdViewDidDismissScreenCallback(IntPtr nativeExpressClient)
         {
             NativeExpressAdClient client = IntPtrToNativeExpressAdClient(nativeExpressClient);
-            client.OnAdClosed(client, EventArgs.Empty);
+            if(client.OnAdClosed != null)
+            {
+                client.OnAdClosed(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADUNativeExpressAdViewWillLeaveApplicationCallback))]
         private static void NativeExpressAdViewWillLeaveApplicationCallback(IntPtr nativeExpressClient)
         {
             NativeExpressAdClient client = IntPtrToNativeExpressAdClient(nativeExpressClient);
-            client.OnAdLeavingApplication(client, EventArgs.Empty);
+            if(client.OnAdLeavingApplication != null)
+            {
+                client.OnAdLeavingApplication(client, EventArgs.Empty);
+            }
         }
 
         private static NativeExpressAdClient IntPtrToNativeExpressAdClient(IntPtr nativeExpressAdClient)
diff --git a/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/RewardBasedVideoAdClient.cs b/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/RewardBasedVideoAdClient.cs
index deab0ff80..82b238f85 100644
--- a/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/RewardBasedVideoAdClient.cs
+++ b/source/plugin/Assets/GoogleMobileAds/Platforms/iOS/RewardBasedVideoAdClient.cs
@@ -146,7 +146,10 @@ private static void RewardBasedVideoAdDidReceiveAdCallback(IntPtr rewardBasedVid
         {
             RewardBasedVideoAdClient client = IntPtrToRewardBasedVideoClient(
                 rewardBasedVideoAdClient);
-            client.OnAdLoaded(client, EventArgs.Empty);
+            if (client.OnAdLoaded != null)
+            {
+                client.OnAdLoaded(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADURewardBasedVideoAdDidFailToReceiveAdWithErrorCallback))]
@@ -155,11 +158,14 @@ private static void RewardBasedVideoAdDidFailToReceiveAdWithErrorCallback(
         {
             RewardBasedVideoAdClient client = IntPtrToRewardBasedVideoClient(
                 rewardBasedVideoAdClient);
-            AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+            if (client.OnAdFailedToLoad != null)
             {
-                Message = error
-            };
-            client.OnAdFailedToLoad(client, args);
+                AdFailedToLoadEventArgs args = new AdFailedToLoadEventArgs()
+                {
+                    Message = error
+                };
+                client.OnAdFailedToLoad(client, args);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADURewardBasedVideoAdDidOpenCallback))]
@@ -167,7 +173,10 @@ private static void RewardBasedVideoAdDidOpenCallback(IntPtr rewardBasedVideoAdC
         {
             RewardBasedVideoAdClient client = IntPtrToRewardBasedVideoClient(
                 rewardBasedVideoAdClient);
-            client.OnAdOpening(client, EventArgs.Empty);
+            if (client.OnAdOpening != null)
+            {
+                client.OnAdOpening(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADURewardBasedVideoAdDidStartCallback))]
@@ -175,7 +184,10 @@ private static void RewardBasedVideoAdDidStartCallback(IntPtr rewardBasedVideoAd
         {
             RewardBasedVideoAdClient client = IntPtrToRewardBasedVideoClient(
                 rewardBasedVideoAdClient);
-            client.OnAdStarted(client, EventArgs.Empty);
+            if (client.OnAdStarted != null)
+            {
+                client.OnAdStarted(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADURewardBasedVideoAdDidCloseCallback))]
@@ -183,21 +195,27 @@ private static void RewardBasedVideoAdDidCloseCallback(IntPtr rewardBasedVideoAd
         {
             RewardBasedVideoAdClient client = IntPtrToRewardBasedVideoClient(
                 rewardBasedVideoAdClient);
-            client.OnAdClosed(client, EventArgs.Empty);
+            if (client.OnAdClosed != null)
+            {
+                client.OnAdClosed(client, EventArgs.Empty);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADURewardBasedVideoAdDidRewardCallback))]
         private static void RewardBasedVideoAdDidRewardUserCallback(
             IntPtr rewardBasedVideoAdClient, string rewardType, double rewardAmount)
         {
-            Reward args = new Reward()
-            {
-                Type = rewardType,
-                Amount = rewardAmount
-            };
             RewardBasedVideoAdClient client = IntPtrToRewardBasedVideoClient(
                 rewardBasedVideoAdClient);
-            client.OnAdRewarded(client, args);
+            if (client.OnAdRewarded != null)
+            {
+                Reward args = new Reward()
+                {
+                    Type = rewardType,
+                    Amount = rewardAmount
+                };
+                client.OnAdRewarded(client, args);
+            }
         }
 
         [MonoPInvokeCallback(typeof(GADURewardBasedVideoAdWillLeaveApplicationCallback))]
@@ -206,7 +224,10 @@ private static void RewardBasedVideoAdWillLeaveApplicationCallback(
         {
             RewardBasedVideoAdClient client = IntPtrToRewardBasedVideoClient(
                 rewardBasedVideoAdClient);
-            client.OnAdLeavingApplication(client, EventArgs.Empty);
+            if (client.OnAdLeavingApplication != null)
+            {
+                client.OnAdLeavingApplication(client, EventArgs.Empty);
+            }
         }
 
         private static RewardBasedVideoAdClient IntPtrToRewardBasedVideoClient(