diff --git a/app/build.gradle b/app/build.gradle
index 83824889..896e6962 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -79,7 +79,7 @@ dependencies {
     compile(project(':jscl')) {
         exclude(module: 'xercesImpl')
     }
-    compile 'org.solovyev.android:checkout:0.7.5@aar'
+    compile 'org.solovyev.android:checkout:1.0.1'
     compile 'org.solovyev.android:material:0.1.4@aar'
     compile "com.google.android.gms:play-services-ads:${versions.gpsLib}"
     compile "com.google.android.gms:play-services-base:${versions.gpsLib}"
@@ -109,8 +109,10 @@ dependencies {
     androidTestCompile 'com.android.support.test:runner:0.5'
     androidTestCompile 'com.android.support.test:rules:0.5'
     androidTestCompile 'org.hamcrest:hamcrest-library:1.3'
-    androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2.2'
-}
+    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
+        // use version of jsr305 provided by Checkout
+        exclude group: 'com.google.code.findbugs', module: 'jsr305'
+    })}
 
 apt {
     arguments {
diff --git a/app/src/main/java/org/solovyev/android/calculator/AppModule.java b/app/src/main/java/org/solovyev/android/calculator/AppModule.java
index c65aeb9b..4c772b0a 100644
--- a/app/src/main/java/org/solovyev/android/calculator/AppModule.java
+++ b/app/src/main/java/org/solovyev/android/calculator/AppModule.java
@@ -9,28 +9,35 @@ import android.os.Looper;
 import android.preference.PreferenceManager;
 import android.support.annotation.NonNull;
 import android.util.Log;
+
 import com.squareup.otto.Bus;
 import com.squareup.otto.GeneratedHandlerFinder;
-import dagger.Module;
-import dagger.Provides;
-import jscl.JsclMathEngine;
+
 import org.solovyev.android.calculator.language.Languages;
 import org.solovyev.android.calculator.wizard.CalculatorWizards;
-import org.solovyev.android.checkout.*;
+import org.solovyev.android.checkout.Billing;
+import org.solovyev.android.checkout.Checkout;
+import org.solovyev.android.checkout.Inventory;
+import org.solovyev.android.checkout.RobotmediaDatabase;
+import org.solovyev.android.checkout.RobotmediaInventory;
 import org.solovyev.android.plotter.Plot;
 import org.solovyev.android.plotter.Plotter;
 import org.solovyev.android.wizard.Wizards;
 
+import java.io.File;
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.atomic.AtomicInteger;
+
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import javax.inject.Named;
 import javax.inject.Singleton;
-import java.io.File;
-import java.util.Collections;
-import java.util.concurrent.Executor;
-import java.util.concurrent.Executors;
-import java.util.concurrent.ThreadFactory;
-import java.util.concurrent.atomic.AtomicInteger;
+
+import dagger.Module;
+import dagger.Provides;
+import jscl.JsclMathEngine;
 
 @Module
 public class AppModule {
@@ -189,12 +196,6 @@ public class AppModule {
         });
     }
 
-    @Singleton
-    @Provides
-    Products provideProducts() {
-        return Products.create().add(ProductTypes.IN_APP, Collections.singletonList("ad_free"));
-    }
-
     @Singleton
     @Provides
     Typeface provideTypeface() {
diff --git a/app/src/main/java/org/solovyev/android/calculator/ads/AdUi.java b/app/src/main/java/org/solovyev/android/calculator/ads/AdUi.java
index b524aa0a..c1c57724 100644
--- a/app/src/main/java/org/solovyev/android/calculator/ads/AdUi.java
+++ b/app/src/main/java/org/solovyev/android/calculator/ads/AdUi.java
@@ -1,11 +1,12 @@
 package org.solovyev.android.calculator.ads;
 
+import static org.solovyev.android.checkout.ProductTypes.IN_APP;
+
 import android.os.Handler;
 import android.os.Looper;
 import android.support.annotation.NonNull;
 import android.view.View;
-import butterknife.Bind;
-import butterknife.ButterKnife;
+
 import org.solovyev.android.calculator.AdView;
 import org.solovyev.android.calculator.R;
 import org.solovyev.android.checkout.CppCheckout;
@@ -15,7 +16,8 @@ import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import javax.inject.Inject;
 
-import static org.solovyev.android.checkout.ProductTypes.IN_APP;
+import butterknife.Bind;
+import butterknife.ButterKnife;
 
 public class AdUi {
 
@@ -47,13 +49,14 @@ public class AdUi {
         if (adFree != null) {
             updateAdView();
         } else {
-            checkout.loadInventory().whenLoaded(onMainThread(new Inventory.Listener() {
-                @Override
-                public void onLoaded(@Nonnull Inventory.Products products) {
-                    adFree = products.get(IN_APP).isPurchased("ad_free");
-                    updateAdView();
-                }
-            }));
+            checkout.loadInventory(Inventory.Request.create().loadAllPurchases(),
+                    onMainThread(new Inventory.Callback() {
+                        @Override
+                        public void onLoaded(@Nonnull Inventory.Products products) {
+                            adFree = products.get(IN_APP).isPurchased("ad_free");
+                            updateAdView();
+                        }
+                    }));
         }
     }
 
@@ -70,18 +73,18 @@ public class AdUi {
     }
 
     @Nonnull
-    private Inventory.Listener onMainThread(@Nonnull final Inventory.Listener listener) {
-        return new Inventory.Listener() {
+    private Inventory.Callback onMainThread(@Nonnull final Inventory.Callback callback) {
+        return new Inventory.Callback() {
             @Override
             public void onLoaded(@Nonnull final Inventory.Products products) {
                 if (handler.getLooper() == Looper.myLooper()) {
-                    listener.onLoaded(products);
+                    callback.onLoaded(products);
                     return;
                 }
                 handler.post(new Runnable() {
                     @Override
                     public void run() {
-                        listener.onLoaded(products);
+                        callback.onLoaded(products);
                     }
                 });
             }
diff --git a/app/src/main/java/org/solovyev/android/calculator/preferences/PreferencesActivity.java b/app/src/main/java/org/solovyev/android/calculator/preferences/PreferencesActivity.java
index b0bb2b27..22f5aaf7 100644
--- a/app/src/main/java/org/solovyev/android/calculator/preferences/PreferencesActivity.java
+++ b/app/src/main/java/org/solovyev/android/calculator/preferences/PreferencesActivity.java
@@ -8,6 +8,7 @@ import android.support.annotation.NonNull;
 import android.support.annotation.StringRes;
 import android.support.annotation.XmlRes;
 import android.util.SparseArray;
+
 import org.solovyev.android.calculator.App;
 import org.solovyev.android.calculator.AppComponent;
 import org.solovyev.android.calculator.BaseActivity;
@@ -16,7 +17,6 @@ import org.solovyev.android.calculator.language.Languages;
 import org.solovyev.android.checkout.ActivityCheckout;
 import org.solovyev.android.checkout.Billing;
 import org.solovyev.android.checkout.Checkout;
-import org.solovyev.android.checkout.Products;
 
 import javax.annotation.Nonnull;
 import javax.inject.Inject;
@@ -47,8 +47,6 @@ public class PreferencesActivity extends BaseActivity implements SharedPreferenc
     @Inject
     Billing billing;
     @Inject
-    Products products;
-    @Inject
     Languages languages;
 
     public PreferencesActivity() {
@@ -87,7 +85,7 @@ public class PreferencesActivity extends BaseActivity implements SharedPreferenc
                     .commit();
         }
 
-        checkout = Checkout.forActivity(this, billing, products);
+        checkout = Checkout.forActivity(this, billing);
         checkout.start();
     }
 
diff --git a/app/src/main/java/org/solovyev/android/calculator/preferences/PreferencesFragment.java b/app/src/main/java/org/solovyev/android/calculator/preferences/PreferencesFragment.java
index cb499180..f231cad9 100644
--- a/app/src/main/java/org/solovyev/android/calculator/preferences/PreferencesFragment.java
+++ b/app/src/main/java/org/solovyev/android/calculator/preferences/PreferencesFragment.java
@@ -1,5 +1,11 @@
 package org.solovyev.android.calculator.preferences;
 
+import static org.solovyev.android.calculator.App.cast;
+import static org.solovyev.android.calculator.Engine.Preferences.angleUnitName;
+import static org.solovyev.android.calculator.Engine.Preferences.numeralBaseName;
+import static org.solovyev.android.calculator.wizard.CalculatorWizards.DEFAULT_WIZARD_FLOW;
+import static org.solovyev.android.wizard.WizardUi.startWizard;
+
 import android.content.Context;
 import android.content.Intent;
 import android.content.SharedPreferences;
@@ -11,13 +17,16 @@ import android.support.v4.app.FragmentActivity;
 import android.util.SparseArray;
 import android.view.View;
 import android.widget.ListView;
+
 import com.squareup.otto.Bus;
 import com.squareup.otto.Subscribe;
-import jscl.AngleUnit;
-import jscl.JsclMathEngine;
-import jscl.NumeralBase;
-import org.solovyev.android.calculator.*;
+
+import org.solovyev.android.calculator.ActivityLauncher;
+import org.solovyev.android.calculator.AdView;
+import org.solovyev.android.calculator.Engine;
+import org.solovyev.android.calculator.Preferences;
 import org.solovyev.android.calculator.Preferences.Gui.Theme;
+import org.solovyev.android.calculator.R;
 import org.solovyev.android.calculator.feedback.FeedbackReporter;
 import org.solovyev.android.calculator.language.Language;
 import org.solovyev.android.calculator.language.Languages;
@@ -29,17 +38,16 @@ import org.solovyev.android.prefs.StringPreference;
 import org.solovyev.android.wizard.Wizards;
 import org.solovyev.common.text.CharacterMapper;
 
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-import javax.inject.Inject;
 import java.util.Arrays;
 import java.util.List;
 
-import static org.solovyev.android.calculator.App.cast;
-import static org.solovyev.android.calculator.Engine.Preferences.angleUnitName;
-import static org.solovyev.android.calculator.Engine.Preferences.numeralBaseName;
-import static org.solovyev.android.calculator.wizard.CalculatorWizards.DEFAULT_WIZARD_FLOW;
-import static org.solovyev.android.wizard.WizardUi.startWizard;
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import javax.inject.Inject;
+
+import jscl.AngleUnit;
+import jscl.JsclMathEngine;
+import jscl.NumeralBase;
 
 public class PreferencesFragment extends org.solovyev.android.material.preferences.PreferencesFragment implements SharedPreferences.OnSharedPreferenceChangeListener {
 
@@ -114,7 +122,7 @@ public class PreferencesFragment extends org.solovyev.android.material.preferenc
         prepareLanguagePreference(preference);
         prepareThemePreference(preference);
 
-        getCheckout().whenReady(new Checkout.ListenerAdapter() {
+        getCheckout().whenReady(new Checkout.EmptyListener() {
             @Override
             public void onReady(@Nonnull BillingRequests requests) {
                 requests.isPurchased(ProductTypes.IN_APP, "ad_free", new RequestListener<Boolean>() {
diff --git a/app/src/main/java/org/solovyev/android/calculator/preferences/PurchaseDialogActivity.java b/app/src/main/java/org/solovyev/android/calculator/preferences/PurchaseDialogActivity.java
index 801f5eab..2c9c4781 100644
--- a/app/src/main/java/org/solovyev/android/calculator/preferences/PurchaseDialogActivity.java
+++ b/app/src/main/java/org/solovyev/android/calculator/preferences/PurchaseDialogActivity.java
@@ -22,6 +22,8 @@
 
 package org.solovyev.android.calculator.preferences;
 
+import static org.solovyev.android.calculator.App.cast;
+
 import android.app.Activity;
 import android.content.DialogInterface;
 import android.content.Intent;
@@ -30,25 +32,28 @@ import android.support.annotation.NonNull;
 import android.support.v4.app.Fragment;
 import android.support.v7.app.AlertDialog;
 import android.support.v7.app.AppCompatActivity;
+
 import org.solovyev.android.calculator.App;
 import org.solovyev.android.calculator.BaseDialogFragment;
 import org.solovyev.android.calculator.R;
 import org.solovyev.android.calculator.ga.Ga;
-import org.solovyev.android.checkout.*;
+import org.solovyev.android.checkout.ActivityCheckout;
+import org.solovyev.android.checkout.Billing;
+import org.solovyev.android.checkout.BillingRequests;
+import org.solovyev.android.checkout.Checkout;
+import org.solovyev.android.checkout.ProductTypes;
+import org.solovyev.android.checkout.Purchase;
+import org.solovyev.android.checkout.RequestListener;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import javax.inject.Inject;
 
-import static org.solovyev.android.calculator.App.cast;
-
 public class PurchaseDialogActivity extends AppCompatActivity implements RequestListener<Purchase> {
 
     @Inject
     Billing billing;
     @Inject
-    Products products;
-    @Inject
     Ga ga;
     ActivityCheckout checkout;
 
@@ -62,7 +67,7 @@ public class PurchaseDialogActivity extends AppCompatActivity implements Request
             App.showDialog(new PurchaseDialogFragment(), PurchaseDialogFragment.FRAGMENT_TAG, getSupportFragmentManager());
         }
 
-        checkout = Checkout.forActivity(this, billing, products);
+        checkout = Checkout.forActivity(this, billing);
         checkout.start();
         checkout.createPurchaseFlow(this);
     }
@@ -80,7 +85,7 @@ public class PurchaseDialogActivity extends AppCompatActivity implements Request
     }
 
     private void purchase() {
-        checkout.whenReady(new Checkout.ListenerAdapter() {
+        checkout.whenReady(new Checkout.EmptyListener() {
             @Override
             public void onReady(@Nonnull BillingRequests requests) {
                 requests.purchase(ProductTypes.IN_APP, "ad_free", null, checkout.getPurchaseFlow());
diff --git a/app/src/main/java/org/solovyev/android/checkout/CppCheckout.java b/app/src/main/java/org/solovyev/android/checkout/CppCheckout.java
index 59e8fc59..a0945076 100644
--- a/app/src/main/java/org/solovyev/android/checkout/CppCheckout.java
+++ b/app/src/main/java/org/solovyev/android/checkout/CppCheckout.java
@@ -13,8 +13,8 @@ public class CppCheckout extends Checkout {
     private int started = 0;
 
     @Inject
-    public CppCheckout(@NonNull Billing billing, @NonNull Products products) {
-        super(null, billing, products);
+    public CppCheckout(@NonNull Billing billing) {
+        super(null, billing);
     }
 
     @Override