diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index c7bf696b..3cc19714 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -60,10 +60,20 @@
             android:name=".preferences.PreferencesActivity"
             android:label="@string/c_app_settings" />
 
+        <activity
+            android:name=".preferences.PreferencesActivity$Dialog"
+            android:label="@string/c_app_settings"
+            android:theme="@style/Cpp.Theme.Dialog" />
+
         <activity
             android:name=".history.HistoryActivity"
             android:label="@string/c_history" />
 
+        <activity
+            android:name=".history.HistoryActivity$Dialog"
+            android:label="@string/c_history"
+            android:theme="@style/Cpp.Theme.Dialog" />
+
         <activity
             android:name=".errors.FixableErrorsActivity"
             android:excludeFromRecents="true"
@@ -75,17 +85,38 @@
             android:name=".about.AboutActivity"
             android:label="@string/c_about" />
 
+        <activity
+            android:name=".about.AboutActivity$Dialog"
+            android:label="@string/c_about"
+            android:theme="@style/Cpp.Theme.Dialog" />
+
         <activity
             android:name=".functions.FunctionsActivity"
             android:label="@string/c_functions" />
 
+        <activity
+            android:name=".functions.FunctionsActivity$Dialog"
+            android:label="@string/c_functions"
+            android:theme="@style/Cpp.Theme.Dialog" />
+
         <activity
             android:name=".operators.OperatorsActivity"
             android:label="@string/c_operators" />
 
+        <activity
+            android:name=".operators.OperatorsActivity$Dialog"
+            android:label="@string/c_operators"
+            android:theme="@style/Cpp.Theme.Dialog" />
+
         <activity
             android:name=".variables.VariablesActivity"
             android:label="@string/c_vars_and_constants" />
+
+        <activity
+            android:name=".variables.VariablesActivity$Dialog"
+            android:label="@string/c_vars_and_constants"
+            android:theme="@style/Cpp.Theme.Dialog" />
+
         <activity
             android:name=".wizard.WizardActivity"
             android:launchMode="singleTop"
diff --git a/app/src/main/java/org/solovyev/android/calculator/ActivityLauncher.java b/app/src/main/java/org/solovyev/android/calculator/ActivityLauncher.java
index 08ae167a..b11ac5a6 100644
--- a/app/src/main/java/org/solovyev/android/calculator/ActivityLauncher.java
+++ b/app/src/main/java/org/solovyev/android/calculator/ActivityLauncher.java
@@ -47,6 +47,9 @@ import org.solovyev.android.calculator.variables.VariablesFragment;
 import org.solovyev.common.msg.MessageType;
 import org.solovyev.common.text.Strings;
 
+import jscl.math.Generic;
+import jscl.math.function.Constant;
+
 import java.util.Set;
 
 import javax.annotation.Nonnull;
@@ -54,9 +57,6 @@ import javax.annotation.Nullable;
 import javax.inject.Inject;
 import javax.inject.Singleton;
 
-import jscl.math.Generic;
-import jscl.math.function.Constant;
-
 @Singleton
 public final class ActivityLauncher implements CalculatorEventListener {
 
@@ -150,11 +150,11 @@ public final class ActivityLauncher implements CalculatorEventListener {
     }
 
     public void showHistory() {
-        show(getContext(), HistoryActivity.class);
+        show(getContext(), HistoryActivity.getClass(getContext()));
     }
 
     public void showSettings() {
-        show(getContext(), PreferencesActivity.class);
+        show(getContext(), PreferencesActivity.getClass(getContext()));
     }
 
     public void showWidgetSettings() {
@@ -163,11 +163,11 @@ public final class ActivityLauncher implements CalculatorEventListener {
     }
 
     public void showOperators() {
-        show(getContext(), OperatorsActivity.class);
+        show(getContext(), OperatorsActivity.getClass(getContext()));
     }
 
     public void showAbout() {
-        show(getContext(), AboutActivity.class);
+        show(getContext(), AboutActivity.getClass(getContext()));
     }
 
     public void openFacebook() {
@@ -239,11 +239,11 @@ public final class ActivityLauncher implements CalculatorEventListener {
     }
 
     public void showFunctions() {
-        show(getContext(), FunctionsActivity.class);
+        show(getContext(), FunctionsActivity.getClass(getContext()));
     }
 
     public void showVariables() {
-        show(getContext(), VariablesActivity.class);
+        show(getContext(), VariablesActivity.getClass(getContext()));
     }
 
     public void openApp() {
diff --git a/app/src/main/java/org/solovyev/android/calculator/ActivityUi.java b/app/src/main/java/org/solovyev/android/calculator/ActivityUi.java
index 20d9cc16..822a82bb 100644
--- a/app/src/main/java/org/solovyev/android/calculator/ActivityUi.java
+++ b/app/src/main/java/org/solovyev/android/calculator/ActivityUi.java
@@ -22,6 +22,8 @@
 
 package org.solovyev.android.calculator;
 
+import static org.solovyev.android.calculator.App.cast;
+
 import android.app.Activity;
 import android.app.KeyguardManager;
 import android.content.Context;
@@ -29,11 +31,9 @@ import android.content.SharedPreferences;
 import android.content.res.Configuration;
 import android.graphics.Color;
 import android.graphics.Typeface;
-import android.os.Bundle;
 import android.support.annotation.DrawableRes;
 import android.support.annotation.LayoutRes;
 import android.support.design.widget.FloatingActionButton;
-import android.support.v4.app.Fragment;
 import android.support.v7.app.ActionBar;
 import android.support.v7.app.AppCompatActivity;
 import android.support.v7.widget.Toolbar;
@@ -41,8 +41,7 @@ import android.util.DisplayMetrics;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.TextView;
-import butterknife.Bind;
-import butterknife.ButterKnife;
+
 import org.solovyev.android.Activities;
 import org.solovyev.android.Check;
 import org.solovyev.android.Views;
@@ -51,12 +50,12 @@ import org.solovyev.android.calculator.language.Language;
 import org.solovyev.android.calculator.language.Languages;
 import org.solovyev.android.calculator.view.Tabs;
 
+import butterknife.Bind;
+import butterknife.ButterKnife;
+
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import javax.inject.Inject;
-import javax.inject.Named;
-
-import static org.solovyev.android.calculator.App.cast;
 
 public class ActivityUi {
 
@@ -157,10 +156,6 @@ public class ActivityUi {
 
         App.getLanguages().updateContextLocale(activity, false);
 
-        if (activity instanceof CalculatorEventListener) {
-            Locator.getInstance().getCalculator().addCalculatorEventListener((CalculatorEventListener) activity);
-        }
-
         activity.setContentView(layoutId);
         ButterKnife.bind(this, activity);
 
@@ -189,22 +184,6 @@ public class ActivityUi {
     public void onDestroy() {
     }
 
-    public void addTab(@Nonnull Class<? extends Fragment> fragmentClass,
-                       @Nullable Bundle fragmentArgs,
-                       int title) {
-        addTab(fragmentClass, fragmentArgs, activity.getString(title));
-    }
-
-    public void addTab(@Nonnull Class<? extends Fragment> fragmentClass,
-                       @Nullable Bundle fragmentArgs,
-                       @Nonnull CharSequence title) {
-        tabs.addTab(fragmentClass, fragmentArgs, title);
-    }
-
-    public void addTab(@Nonnull FragmentTab tab, @Nullable Bundle fragmentArgs) {
-        addTab(tab.type, fragmentArgs, tab.title);
-    }
-
     @Nonnull
     public Language getLanguage() {
         return language;
diff --git a/app/src/main/java/org/solovyev/android/calculator/Preferences.java b/app/src/main/java/org/solovyev/android/calculator/Preferences.java
index 73bbf8ff..66240de3 100644
--- a/app/src/main/java/org/solovyev/android/calculator/Preferences.java
+++ b/app/src/main/java/org/solovyev/android/calculator/Preferences.java
@@ -41,8 +41,14 @@ import android.util.SparseArray;
 import android.view.ContextThemeWrapper;
 
 import org.solovyev.android.Check;
+import org.solovyev.android.calculator.about.AboutActivity;
+import org.solovyev.android.calculator.functions.FunctionsActivity;
+import org.solovyev.android.calculator.history.HistoryActivity;
 import org.solovyev.android.calculator.language.Languages;
 import org.solovyev.android.calculator.math.MathType;
+import org.solovyev.android.calculator.operators.OperatorsActivity;
+import org.solovyev.android.calculator.preferences.PreferencesActivity;
+import org.solovyev.android.calculator.variables.VariablesActivity;
 import org.solovyev.android.calculator.wizard.WizardActivity;
 import org.solovyev.android.prefs.BooleanPreference;
 import org.solovyev.android.prefs.IntegerPreference;
@@ -334,7 +340,24 @@ public final class Preferences {
                 if (context instanceof WizardActivity) {
                     return wizardTheme;
                 }
-                final boolean tablet = context.getResources().getBoolean(R.bool.cpp_tablet);
+                if (context instanceof FunctionsActivity.Dialog) {
+                    return dialogTheme;
+                }
+                if (context instanceof PreferencesActivity.Dialog) {
+                    return dialogTheme;
+                }
+                if (context instanceof VariablesActivity.Dialog) {
+                    return dialogTheme;
+                }
+                if (context instanceof OperatorsActivity.Dialog) {
+                    return dialogTheme;
+                }
+                if (context instanceof HistoryActivity.Dialog) {
+                    return dialogTheme;
+                }
+                if (context instanceof AboutActivity.Dialog) {
+                    return dialogTheme;
+                }
                 return theme;
             }
 
diff --git a/app/src/main/java/org/solovyev/android/calculator/about/AboutActivity.java b/app/src/main/java/org/solovyev/android/calculator/about/AboutActivity.java
index 26eabb3b..be2f0f4d 100644
--- a/app/src/main/java/org/solovyev/android/calculator/about/AboutActivity.java
+++ b/app/src/main/java/org/solovyev/android/calculator/about/AboutActivity.java
@@ -22,14 +22,28 @@
 
 package org.solovyev.android.calculator.about;
 
+import android.content.Context;
+import android.support.annotation.NonNull;
+
 import org.solovyev.android.calculator.BaseActivity;
 import org.solovyev.android.calculator.FragmentTab;
+import org.solovyev.android.calculator.R;
 import org.solovyev.android.calculator.view.Tabs;
 
 import javax.annotation.Nonnull;
 
 public class AboutActivity extends BaseActivity {
 
+    public static class Dialog extends AboutActivity {
+    }
+
+    @Nonnull
+    public static Class<? extends AboutActivity> getClass(@NonNull Context context) {
+        boolean tablet = context.getResources().getBoolean(R.bool.cpp_tablet);
+        return tablet ? Dialog.class : AboutActivity.class;
+    }
+
+
     @Override
     protected void populateTabs(@Nonnull Tabs tabs) {
         super.populateTabs(tabs);
diff --git a/app/src/main/java/org/solovyev/android/calculator/functions/EditFunctionFragment.java b/app/src/main/java/org/solovyev/android/calculator/functions/EditFunctionFragment.java
index ee0602b5..4fcc5033 100644
--- a/app/src/main/java/org/solovyev/android/calculator/functions/EditFunctionFragment.java
+++ b/app/src/main/java/org/solovyev/android/calculator/functions/EditFunctionFragment.java
@@ -22,6 +22,8 @@
 
 package org.solovyev.android.calculator.functions;
 
+import static org.solovyev.android.calculator.functions.CppFunction.NO_ID;
+
 import android.annotation.SuppressLint;
 import android.content.Context;
 import android.content.DialogInterface;
@@ -35,26 +37,47 @@ import android.support.v4.app.FragmentManager;
 import android.support.v7.app.AlertDialog;
 import android.text.Editable;
 import android.text.TextUtils;
-import android.view.*;
+import android.view.ContextMenu;
+import android.view.KeyEvent;
+import android.view.LayoutInflater;
+import android.view.Menu;
+import android.view.MenuItem;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.ViewParent;
 import android.view.inputmethod.InputMethodManager;
 import android.widget.EditText;
-import butterknife.Bind;
-import butterknife.ButterKnife;
-import jscl.math.function.Function;
+
 import org.solovyev.android.Activities;
 import org.solovyev.android.Check;
-import org.solovyev.android.calculator.*;
+import org.solovyev.android.calculator.App;
+import org.solovyev.android.calculator.AppComponent;
+import org.solovyev.android.calculator.BaseDialogFragment;
+import org.solovyev.android.calculator.Calculator;
+import org.solovyev.android.calculator.Engine;
+import org.solovyev.android.calculator.FloatingCalculatorKeyboard;
+import org.solovyev.android.calculator.Keyboard;
+import org.solovyev.android.calculator.ParseException;
+import org.solovyev.android.calculator.R;
+import org.solovyev.android.calculator.VariablesRegistry;
 import org.solovyev.android.calculator.entities.EntityRemovalDialog;
 import org.solovyev.android.calculator.keyboard.FloatingKeyboardWindow;
 import org.solovyev.android.calculator.view.EditTextCompat;
 import org.solovyev.common.math.MathRegistry;
 
+import butterknife.Bind;
+import butterknife.ButterKnife;
+import jscl.math.function.Function;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import javax.inject.Inject;
-import java.util.*;
-
-import static org.solovyev.android.calculator.functions.CppFunction.NO_ID;
 
 public class EditFunctionFragment extends BaseDialogFragment implements View.OnClickListener, View.OnFocusChangeListener, View.OnKeyListener {
 
@@ -107,7 +130,7 @@ public class EditFunctionFragment extends BaseDialogFragment implements View.OnC
 
     public static void show(@Nullable CppFunction function, @Nonnull Context context) {
         if (!(context instanceof FunctionsActivity)) {
-            final Intent intent = new Intent(context, FunctionsActivity.class);
+            final Intent intent = new Intent(context, FunctionsActivity.getClass(context));
             Activities.addIntentFlags(intent, false, context);
             intent.putExtra(FunctionsActivity.EXTRA_FUNCTION, function);
             context.startActivity(intent);
diff --git a/app/src/main/java/org/solovyev/android/calculator/functions/FunctionsActivity.java b/app/src/main/java/org/solovyev/android/calculator/functions/FunctionsActivity.java
index bb4bf6f4..acc8ed30 100644
--- a/app/src/main/java/org/solovyev/android/calculator/functions/FunctionsActivity.java
+++ b/app/src/main/java/org/solovyev/android/calculator/functions/FunctionsActivity.java
@@ -22,8 +22,11 @@
 
 package org.solovyev.android.calculator.functions;
 
+import android.content.Context;
 import android.os.Bundle;
+import android.support.annotation.NonNull;
 import android.view.View;
+
 import org.solovyev.android.calculator.BaseActivity;
 import org.solovyev.android.calculator.FragmentTab;
 import org.solovyev.android.calculator.R;
@@ -36,6 +39,12 @@ public class FunctionsActivity extends BaseActivity {
 
     public static final String EXTRA_FUNCTION = "function";
 
+    @Nonnull
+    public static Class<? extends FunctionsActivity> getClass(@NonNull Context context) {
+        boolean tablet = context.getResources().getBoolean(R.bool.cpp_tablet);
+        return tablet ? Dialog.class : FunctionsActivity.class;
+    }
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -74,4 +83,7 @@ public class FunctionsActivity extends BaseActivity {
             tabs.addTab(category, FragmentTab.operators, title);
         }
     }
+
+    public static final class Dialog extends FunctionsActivity {
+    }
 }
\ No newline at end of file
diff --git a/app/src/main/java/org/solovyev/android/calculator/history/HistoryActivity.java b/app/src/main/java/org/solovyev/android/calculator/history/HistoryActivity.java
index 63109b87..3993d5dc 100644
--- a/app/src/main/java/org/solovyev/android/calculator/history/HistoryActivity.java
+++ b/app/src/main/java/org/solovyev/android/calculator/history/HistoryActivity.java
@@ -22,21 +22,38 @@
 
 package org.solovyev.android.calculator.history;
 
+import static org.solovyev.android.calculator.FragmentTab.saved_history;
+
+import android.content.Context;
 import android.content.DialogInterface;
 import android.os.Bundle;
+import android.support.annotation.NonNull;
 import android.support.v4.app.Fragment;
 import android.support.v7.app.AlertDialog;
 import android.view.View;
-import org.solovyev.android.calculator.*;
+
+import org.solovyev.android.calculator.App;
+import org.solovyev.android.calculator.AppComponent;
+import org.solovyev.android.calculator.BaseActivity;
+import org.solovyev.android.calculator.FragmentTab;
+import org.solovyev.android.calculator.R;
 import org.solovyev.android.calculator.view.Tabs;
 
 import javax.annotation.Nonnull;
 import javax.inject.Inject;
 
-import static org.solovyev.android.calculator.FragmentTab.saved_history;
-
 public class HistoryActivity extends BaseActivity {
 
+    public static class Dialog extends HistoryActivity {
+    }
+
+    @Nonnull
+    public static Class<? extends HistoryActivity> getClass(@NonNull Context context) {
+        boolean tablet = context.getResources().getBoolean(R.bool.cpp_tablet);
+        return tablet ? Dialog.class : HistoryActivity.class;
+    }
+
+
     @Inject
     History history;
 
diff --git a/app/src/main/java/org/solovyev/android/calculator/operators/OperatorsActivity.java b/app/src/main/java/org/solovyev/android/calculator/operators/OperatorsActivity.java
index ec93b733..5a0a9a5d 100644
--- a/app/src/main/java/org/solovyev/android/calculator/operators/OperatorsActivity.java
+++ b/app/src/main/java/org/solovyev/android/calculator/operators/OperatorsActivity.java
@@ -22,14 +22,27 @@
 
 package org.solovyev.android.calculator.operators;
 
+import android.content.Context;
+import android.support.annotation.NonNull;
+
 import org.solovyev.android.calculator.BaseActivity;
 import org.solovyev.android.calculator.FragmentTab;
+import org.solovyev.android.calculator.R;
 import org.solovyev.android.calculator.view.Tabs;
 
 import javax.annotation.Nonnull;
 
 public class OperatorsActivity extends BaseActivity {
 
+    public static class Dialog extends OperatorsActivity {
+    }
+
+    @Nonnull
+    public static Class<? extends OperatorsActivity> getClass(@NonNull Context context) {
+        boolean tablet = context.getResources().getBoolean(R.bool.cpp_tablet);
+        return tablet ? Dialog.class : OperatorsActivity.class;
+    }
+
     @Override
     protected void populateTabs(@Nonnull Tabs tabs) {
         super.populateTabs(tabs);
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 a24c3480..f2ca9248 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
@@ -4,6 +4,7 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.os.Bundle;
+import android.support.annotation.NonNull;
 import android.support.annotation.StringRes;
 import android.support.annotation.XmlRes;
 import android.util.SparseArray;
@@ -30,6 +31,11 @@ public class PreferencesActivity extends BaseActivity implements SharedPreferenc
     @Nonnull
     private static final SparseArray<PrefDef> preferences = new SparseArray<>();
 
+    public static Class<? extends PreferencesActivity> getClass(@NonNull Context context) {
+        final boolean tablet = context.getResources().getBoolean(R.bool.cpp_tablet);
+        return tablet ? Dialog.class : PreferencesActivity.class;
+    }
+
     static {
         preferences.append(R.xml.preferences, new PrefDef("screen-main", R.string.c_app_settings));
         preferences.append(R.xml.preferences_calculations, new PrefDef("screen-calculations", R.string.c_prefs_calculations_category));
@@ -68,7 +74,7 @@ public class PreferencesActivity extends BaseActivity implements SharedPreferenc
 
     @Nonnull
     public static Intent makeIntent(@Nonnull Context context, @XmlRes int preference, @StringRes int title) {
-        final Intent intent = new Intent(context, PreferencesActivity.class);
+        final Intent intent = new Intent(context, getClass(context));
         intent.putExtra(EXTRA_PREFERENCE, preference);
         if (title != 0) {
             intent.putExtra(EXTRA_PREFERENCE_TITLE, title);
@@ -150,4 +156,7 @@ public class PreferencesActivity extends BaseActivity implements SharedPreferenc
             this.title = title;
         }
     }
+
+    public static final class Dialog extends PreferencesActivity {
+    }
 }
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 45ea65d3..b793dd8e 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
@@ -1,15 +1,24 @@
 package org.solovyev.android.calculator.preferences;
 
+import static org.solovyev.android.calculator.wizard.CalculatorWizards.DEFAULT_WIZARD_FLOW;
+import static org.solovyev.android.wizard.WizardUi.startWizard;
+
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.os.Build;
 import android.os.Bundle;
 import android.preference.ListPreference;
 import android.preference.Preference;
+import android.support.v4.app.FragmentActivity;
 import android.util.SparseArray;
 import android.view.View;
 import android.widget.ListView;
-import org.solovyev.android.calculator.*;
+
+import org.solovyev.android.calculator.AdView;
+import org.solovyev.android.calculator.App;
+import org.solovyev.android.calculator.Engine;
+import org.solovyev.android.calculator.Preferences;
+import org.solovyev.android.calculator.R;
 import org.solovyev.android.calculator.language.Language;
 import org.solovyev.android.calculator.language.Languages;
 import org.solovyev.android.checkout.BillingRequests;
@@ -17,12 +26,10 @@ import org.solovyev.android.checkout.Checkout;
 import org.solovyev.android.checkout.ProductTypes;
 import org.solovyev.android.checkout.RequestListener;
 
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
 import java.util.List;
 
-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;
 
 public class PreferencesFragment extends org.solovyev.android.material.preferences.PreferencesFragment implements SharedPreferences.OnSharedPreferenceChangeListener {
 
@@ -49,7 +56,8 @@ public class PreferencesFragment extends org.solovyev.android.material.preferenc
     private void setPreferenceIntent(int xml, @Nonnull PreferencesActivity.PrefDef def) {
         final Preference preference = findPreference(def.id);
         if (preference != null) {
-            final Intent intent = new Intent(getActivity(), PreferencesActivity.class);
+            final FragmentActivity context = getActivity();
+            final Intent intent = new Intent(context, PreferencesActivity.getClass(context));
             intent.putExtra(PreferencesActivity.EXTRA_PREFERENCE, xml);
             intent.putExtra(PreferencesActivity.EXTRA_PREFERENCE_TITLE, def.title);
             preference.setIntent(intent);
diff --git a/app/src/main/java/org/solovyev/android/calculator/variables/EditVariableFragment.java b/app/src/main/java/org/solovyev/android/calculator/variables/EditVariableFragment.java
index 14014b2e..846f41fa 100644
--- a/app/src/main/java/org/solovyev/android/calculator/variables/EditVariableFragment.java
+++ b/app/src/main/java/org/solovyev/android/calculator/variables/EditVariableFragment.java
@@ -22,6 +22,8 @@
 
 package org.solovyev.android.calculator.variables;
 
+import static org.solovyev.android.calculator.variables.CppVariable.NO_ID;
+
 import android.annotation.SuppressLint;
 import android.content.Context;
 import android.content.DialogInterface;
@@ -41,12 +43,17 @@ import android.view.inputmethod.InputMethodManager;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.PopupWindow;
-import butterknife.Bind;
-import butterknife.ButterKnife;
-import jscl.math.function.IConstant;
+
 import org.solovyev.android.Activities;
 import org.solovyev.android.Check;
-import org.solovyev.android.calculator.*;
+import org.solovyev.android.calculator.App;
+import org.solovyev.android.calculator.AppComponent;
+import org.solovyev.android.calculator.BaseDialogFragment;
+import org.solovyev.android.calculator.Calculator;
+import org.solovyev.android.calculator.Engine;
+import org.solovyev.android.calculator.Keyboard;
+import org.solovyev.android.calculator.R;
+import org.solovyev.android.calculator.VariablesRegistry;
 import org.solovyev.android.calculator.entities.EntityRemovalDialog;
 import org.solovyev.android.calculator.functions.FunctionsRegistry;
 import org.solovyev.android.calculator.keyboard.FloatingKeyboard;
@@ -55,13 +62,16 @@ import org.solovyev.android.calculator.math.MathType;
 import org.solovyev.android.calculator.view.EditTextCompat;
 import org.solovyev.common.text.Strings;
 
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-import javax.inject.Inject;
+import butterknife.Bind;
+import butterknife.ButterKnife;
+import jscl.math.function.IConstant;
+
 import java.util.Arrays;
 import java.util.List;
 
-import static org.solovyev.android.calculator.variables.CppVariable.NO_ID;
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import javax.inject.Inject;
 
 public class EditVariableFragment extends BaseDialogFragment implements View.OnFocusChangeListener, View.OnKeyListener, View.OnClickListener {
 
@@ -119,7 +129,7 @@ public class EditVariableFragment extends BaseDialogFragment implements View.OnF
 
     public static void showDialog(@Nullable CppVariable variable, @Nonnull Context context) {
         if (!(context instanceof VariablesActivity)) {
-            final Intent intent = new Intent(context, VariablesActivity.class);
+            final Intent intent = new Intent(context, VariablesActivity.getClass(context));
             Activities.addIntentFlags(intent, false, context);
             intent.putExtra(VariablesActivity.EXTRA_VARIABLE, variable);
             context.startActivity(intent);
diff --git a/app/src/main/java/org/solovyev/android/calculator/variables/VariablesActivity.java b/app/src/main/java/org/solovyev/android/calculator/variables/VariablesActivity.java
index ca5949f4..b55866dc 100644
--- a/app/src/main/java/org/solovyev/android/calculator/variables/VariablesActivity.java
+++ b/app/src/main/java/org/solovyev/android/calculator/variables/VariablesActivity.java
@@ -22,7 +22,9 @@
 
 package org.solovyev.android.calculator.variables;
 
+import android.content.Context;
 import android.os.Bundle;
+import android.support.annotation.NonNull;
 import android.view.View;
 import org.solovyev.android.calculator.BaseActivity;
 import org.solovyev.android.calculator.FragmentTab;
@@ -36,6 +38,12 @@ public class VariablesActivity extends BaseActivity {
 
     public static final String EXTRA_VARIABLE = "variable";
 
+    @Nonnull
+    public static Class<? extends VariablesActivity> getClass(@NonNull Context context) {
+        boolean tablet = context.getResources().getBoolean(R.bool.cpp_tablet);
+        return tablet ? Dialog.class : VariablesActivity.class;
+    }
+
     @Override
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -63,4 +71,7 @@ public class VariablesActivity extends BaseActivity {
             tabs.addTab(category, FragmentTab.variables);
         }
     }
+
+    public static final class Dialog extends VariablesActivity {
+    }
 }
diff --git a/app/src/main/res/layout-sw600dp/activity_tabs.xml b/app/src/main/res/layout-sw600dp/activity_tabs.xml
new file mode 100644
index 00000000..a6861469
--- /dev/null
+++ b/app/src/main/res/layout-sw600dp/activity_tabs.xml
@@ -0,0 +1,66 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  ~ Copyright 2013 serso aka se.solovyev
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~    http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  ~
+  ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+  ~ Contact details
+  ~
+  ~ Email: se.solovyev@gmail.com
+  ~ Site:  http://se.solovyev.org
+  -->
+
+<android.support.design.widget.CoordinatorLayout
+    android:id="@+id/main"
+    style="@style/CppMain"
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
+    <android.support.v4.view.ViewPager
+        android:id="@+id/viewPager"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        app:layout_behavior="@string/appbar_scrolling_view_behavior" />
+
+    <android.support.design.widget.AppBarLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content">
+
+        <android.support.v7.widget.Toolbar
+            android:id="@+id/toolbar"
+            style="?cpp_toolbar_style"
+            android:layout_width="match_parent"
+            android:layout_height="?actionBarSize" />
+
+        <android.support.design.widget.TabLayout
+            android:id="@+id/tabs"
+            style="?cpp_toolbar_style"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:overScrollMode="never"
+            app:tabGravity="fill"
+            app:tabMaxWidth="0dp"
+            app:tabMode="fixed" />
+
+    </android.support.design.widget.AppBarLayout>
+
+    <android.support.design.widget.FloatingActionButton
+        app:layout_behavior="org.solovyev.android.calculator.view.PagerViewFabBehavior"
+        android:id="@+id/fab"
+        style="@style/CppFab" />
+
+</android.support.design.widget.CoordinatorLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/fragment_preferences.xml b/app/src/main/res/layout/fragment_preferences.xml
index 1ebddba6..5d273ddc 100644
--- a/app/src/main/res/layout/fragment_preferences.xml
+++ b/app/src/main/res/layout/fragment_preferences.xml
@@ -3,6 +3,4 @@
 <ListView
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:id="@android:id/list"
-    style="@style/CppListView"
-    android:layout_width="match_parent"
-    android:layout_height="match_parent" />
\ No newline at end of file
+    style="@style/CppListView"/>
\ No newline at end of file
diff --git a/app/src/main/res/values/styles.xml b/app/src/main/res/values/styles.xml
index ed2144be..ab71723b 100644
--- a/app/src/main/res/values/styles.xml
+++ b/app/src/main/res/values/styles.xml
@@ -322,7 +322,7 @@
         <item name="android:dividerHeight">1px</item>
         <item name="android:divider">@drawable/divider</item>
         <item name="android:cacheColorHint">@android:color/transparent</item>
-        <item name="android:layout_height">match_parent</item>
+        <item name="android:layout_height">wrap_content</item>
         <item name="android:layout_width">match_parent</item>
         <item name="android:layout_weight">1</item>
         <item name="android:fadingEdge">none</item>
diff --git a/app/src/main/res/values/theme.xml b/app/src/main/res/values/theme.xml
index 3c854695..aad98ea8 100644
--- a/app/src/main/res/values/theme.xml
+++ b/app/src/main/res/values/theme.xml
@@ -40,22 +40,19 @@
         <item name="android:listDivider">@drawable/divider_dark</item>
     </style>
 
-    <style name="Cpp.Theme.Translucent" parent="Cpp.Theme.Dialog">
-        <item name="windowActionBar">false</item>
-        <item name="windowNoTitle">true</item>
-        <item name="android:windowNoTitle">true</item>
-        <item name="android:windowIsTranslucent">true</item>
-    </style>
+    <style name="Cpp.Theme.Translucent" parent="Cpp.Theme.Dialog"/>
+
+    <style name="Cpp.Theme.Dialog" parent="@style/Theme.AppCompat.DialogWhenLarge">
+        <item name="android:windowBackground">@color/cpp_main_bg</item>
 
-    <style name="Cpp.Theme.Dialog" parent="@style/Theme.AppCompat.Dialog">
         <item name="colorPrimary">@color/cpp_metro_button</item>
         <item name="colorPrimaryDark">@color/cpp_metro_button_dark</item>
         <item name="colorAccent">@color/cpp_material_accent</item>
 
         <item name="windowNoTitle">true</item>
         <item name="android:windowNoTitle">true</item>
-        <item name="android:windowTitleBackgroundStyle">@android:color/transparent</item>
         <item name="windowActionBar">false</item>
+        <item name="android:windowIsTranslucent">true</item>
 
         <item name="cpp_main_bg">@color/cpp_main_bg</item>
         <item name="cpp_pane_bg">@drawable/pane</item>
@@ -100,15 +97,17 @@
         <item name="android:listDivider">@drawable/divider</item>
     </style>
 
-    <style name="Cpp.Theme.Light.Dialog" parent="@style/Theme.AppCompat.Light.Dialog">
+    <style name="Cpp.Theme.Light.Dialog" parent="@style/Theme.AppCompat.Light.DialogWhenLarge">
+        <item name="android:windowBackground">@color/cpp_main_bg_light</item>
+
         <item name="colorPrimary">@color/cpp_material_light</item>
         <item name="colorPrimaryDark">@color/cpp_material_light</item>
         <item name="colorAccent">@color/cpp_material_light</item>
 
         <item name="windowNoTitle">true</item>
         <item name="android:windowNoTitle">true</item>
-        <item name="android:windowTitleBackgroundStyle">@android:color/transparent</item>
         <item name="windowActionBar">false</item>
+        <item name="android:windowIsTranslucent">true</item>
 
         <item name="cpp_main_bg">@color/cpp_main_bg_light</item>
         <item name="cpp_pane_bg">@drawable/pane_light</item>