diff --git a/src/com/example/android/trivialdrivesample/util/IabHelper.java b/src/com/example/android/trivialdrivesample/util/IabHelper.java
index 3602bcc..a3d6249 100644
--- a/src/com/example/android/trivialdrivesample/util/IabHelper.java
+++ b/src/com/example/android/trivialdrivesample/util/IabHelper.java
@@ -22,6 +22,8 @@
 import android.content.Intent;
 import android.content.IntentSender.SendIntentException;
 import android.content.ServiceConnection;
+import android.content.pm.PackageManager;
+import android.content.pm.ResolveInfo;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.IBinder;
@@ -218,7 +220,12 @@ public void onServiceDisconnected(ComponentName name) {
             public void onServiceConnected(ComponentName name, IBinder service) {
                 if (mDisposed) return;
                 logDebug("Billing service connected.");
-                mService = IInAppBillingService.Stub.asInterface(service);
+                if (!"com.farsitel.bazaar".equals(name.getPackageName())) {
+                    logDebug("can't find bazaar app!");
+                    return;
+                } else {
+                    mService = IInAppBillingService.Stub.asInterface(service);
+                }
                 String packageName = mContext.getPackageName();
                 try {
                     logDebug("Checking for in-app billing 3 support.");
@@ -264,7 +271,9 @@ public void onServiceConnected(ComponentName name, IBinder service) {
 
         Intent serviceIntent = new Intent("ir.cafebazaar.pardakht.InAppBillingService.BIND");
         serviceIntent.setPackage("com.farsitel.bazaar");
-        if (!mContext.getPackageManager().queryIntentServices(serviceIntent, 0).isEmpty()) {
+        PackageManager pm=mContext.getPackageManager();
+        List<ResolveInfo> intentServices = pm.queryIntentServices(serviceIntent, 0);
+        if (intentServices != null && !intentServices.isEmpty()) {
             // service available to handle that Intent
             mContext.bindService(serviceIntent, mServiceConn, Context.BIND_AUTO_CREATE);
         }
@@ -287,7 +296,7 @@ public void onServiceConnected(ComponentName name, IBinder service) {
     public void dispose() {
         logDebug("Disposing.");
         mSetupDone = false;
-        if (mServiceConn != null) {
+        if (mServiceConn != null && mService!=null) {
             logDebug("Unbinding from service.");
             if (mContext != null) mContext.unbindService(mServiceConn);
         }