diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 42fe7268..2a09e020 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -125,10 +125,6 @@
             android:label="@string/cpp_purchase_title"
             android:theme="@style/Cpp.Theme.Material.Dialog" />
 
-        <activity
-            android:name=".CalculatorDialogActivity"
-            android:theme="@style/Cpp.Theme.Material.Dialog" />
-
         <!-- todo serso: strings-->
         <activity
             android:name=".matrix.CalculatorMatrixActivity"
diff --git a/app/src/main/java/org/solovyev/android/calculator/CalculatorActivityLauncher.java b/app/src/main/java/org/solovyev/android/calculator/CalculatorActivityLauncher.java
index 904d02ac..807a0503 100644
--- a/app/src/main/java/org/solovyev/android/calculator/CalculatorActivityLauncher.java
+++ b/app/src/main/java/org/solovyev/android/calculator/CalculatorActivityLauncher.java
@@ -287,18 +287,6 @@ public final class CalculatorActivityLauncher implements CalculatorEventListener
                     });
                 }
                 break;
-            case show_message_dialog:
-                final DialogData dialogData = (DialogData) data;
-                if (dialogData != null) {
-                    App.getUiThreadExecutor().execute(new Runnable() {
-                        @Override
-                        public void run() {
-                            CalculatorDialogActivity.showDialog(context, dialogData);
-                        }
-                    });
-                }
-                break;
-
         }
     }
 }
diff --git a/app/src/main/java/org/solovyev/android/calculator/CalculatorDialogActivity.java b/app/src/main/java/org/solovyev/android/calculator/CalculatorDialogActivity.java
deleted file mode 100644
index 61b375a0..00000000
--- a/app/src/main/java/org/solovyev/android/calculator/CalculatorDialogActivity.java
+++ /dev/null
@@ -1,151 +0,0 @@
-/*
- * 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
- */
-
-package org.solovyev.android.calculator;
-
-import android.content.Context;
-import android.content.Intent;
-import android.os.Bundle;
-import android.os.Parcelable;
-import android.support.v7.app.ActionBarActivity;
-import android.text.method.ScrollingMovementMethod;
-import android.view.View;
-import android.widget.Button;
-import android.widget.TextView;
-
-import org.solovyev.android.Android;
-import org.solovyev.android.fragments.FragmentUtils;
-import org.solovyev.common.msg.MessageType;
-import org.solovyev.common.text.Strings;
-
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-
-/**
- * User: serso
- * Date: 1/20/13
- * Time: 12:50 PM
- */
-public class CalculatorDialogActivity extends ActionBarActivity {
-
-    @Nonnull
-    private static final String TAG = CalculatorDialogActivity.class.getSimpleName();
-
-    @Nonnull
-    private static final String DIALOG_DATA_EXTRA = "dialog_data";
-
-    public static void showDialog(@Nonnull Context context, @Nonnull DialogData dialogData) {
-        final Intent intent = new Intent();
-        intent.setClass(context, CalculatorDialogActivity.class);
-        intent.putExtra(DIALOG_DATA_EXTRA, ParcelableDialogData.wrap(dialogData));
-        Android.addIntentFlags(intent, false, context);
-        context.startActivity(intent);
-    }
-
-    @Nullable
-    private static DialogData readDialogData(@Nullable Intent in) {
-        if (in != null) {
-            final Parcelable parcelable = in.getParcelableExtra(DIALOG_DATA_EXTRA);
-            if (parcelable instanceof DialogData) {
-                return (DialogData) parcelable;
-            }
-        }
-
-        return null;
-    }
-
-    @Nullable
-    private static DialogData readDialogData(@Nullable Bundle in) {
-        if (in != null) {
-            final Parcelable parcelable = in.getParcelable(DIALOG_DATA_EXTRA);
-            if (parcelable instanceof DialogData) {
-                return (DialogData) parcelable;
-            }
-        }
-
-        return null;
-    }
-
-    @Override
-    protected void onCreate(@Nullable Bundle in) {
-        super.onCreate(in);
-
-        final DialogData dialogData = readDialogData(getIntent());
-        if (dialogData == null) {
-            this.finish();
-        } else {
-            setContentView(R.layout.cpp_dialog);
-
-            final String title = dialogData.getTitle();
-            if (!Strings.isEmpty(title)) {
-                setTitle(title);
-            }
-
-
-            final Bundle args = new Bundle();
-            args.putParcelable(DIALOG_DATA_EXTRA, ParcelableDialogData.wrap(dialogData));
-            FragmentUtils.createFragment(this, CalculatorDialogFragment.class, R.id.dialog_layout, "dialog", args);
-        }
-    }
-
-    public static class CalculatorDialogFragment extends CalculatorFragment {
-
-        public CalculatorDialogFragment() {
-            super(CalculatorFragmentType.dialog);
-        }
-
-        @Override
-        public void onViewCreated(@Nonnull View root, Bundle savedInstanceState) {
-            super.onViewCreated(root, savedInstanceState);
-
-            final DialogData dialogData = readDialogData(getArguments());
-
-            if (dialogData != null) {
-                final TextView messageTextView = (TextView) root.findViewById(R.id.cpp_dialog_message_textview);
-                messageTextView.setMovementMethod(ScrollingMovementMethod.getInstance());
-                messageTextView.setText(dialogData.getMessage());
-
-                if (dialogData.getMessageLevel() == MessageType.error || dialogData.getMessageLevel() == MessageType.warning) {
-                    final Button copyButton = (Button) root.findViewById(R.id.cpp_copy_button);
-                    copyButton.setVisibility(View.VISIBLE);
-                    copyButton.setOnClickListener(new View.OnClickListener() {
-                        @Override
-                        public void onClick(View v) {
-                            Locator.getInstance().getClipboard().setText(dialogData.getMessage());
-                            Locator.getInstance().getNotifier().showMessage(CalculatorMessage.newInfoMessage(CalculatorMessages.text_copied));
-                        }
-                    });
-
-                }
-            }
-
-            root.findViewById(R.id.cpp_ok_button).setOnClickListener(new View.OnClickListener() {
-                @Override
-                public void onClick(View v) {
-                    getActivity().finish();
-                }
-            });
-        }
-    }
-
-}
-
diff --git a/app/src/main/java/org/solovyev/android/calculator/CalculatorEventType.java b/app/src/main/java/org/solovyev/android/calculator/CalculatorEventType.java
index ae66b942..6b6f032a 100644
--- a/app/src/main/java/org/solovyev/android/calculator/CalculatorEventType.java
+++ b/app/src/main/java/org/solovyev/android/calculator/CalculatorEventType.java
@@ -116,11 +116,6 @@ public enum CalculatorEventType {
     show_create_matrix_dialog,
     show_create_function_dialog,
 
-    /**
-     * {@link DialogData}
-     */
-    show_message_dialog,
-
     plot_graph,
 
     /**
diff --git a/app/src/main/java/org/solovyev/android/calculator/CalculatorFragmentType.java b/app/src/main/java/org/solovyev/android/calculator/CalculatorFragmentType.java
index a7b5faa5..a4456a18 100644
--- a/app/src/main/java/org/solovyev/android/calculator/CalculatorFragmentType.java
+++ b/app/src/main/java/org/solovyev/android/calculator/CalculatorFragmentType.java
@@ -62,8 +62,6 @@ public enum CalculatorFragmentType {
 
     purchase_dialog(PurchaseDialogActivity.PurchaseDialogFragment.class, R.layout.cpp_purchase_dialog_fragment, R.string.cpp_purchase_title),
 
-    dialog(CalculatorDialogActivity.CalculatorDialogFragment.class, R.layout.cpp_dialog_fragment, R.string.cpp_message),
-
     about(CalculatorAboutFragment.class, R.layout.about_fragment, R.string.c_about),
 
     // todo serso: strings
diff --git a/app/src/main/java/org/solovyev/android/calculator/DialogData.java b/app/src/main/java/org/solovyev/android/calculator/DialogData.java
deleted file mode 100644
index d530a913..00000000
--- a/app/src/main/java/org/solovyev/android/calculator/DialogData.java
+++ /dev/null
@@ -1,45 +0,0 @@
-/*
- * 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
- */
-
-package org.solovyev.android.calculator;
-
-import org.solovyev.common.msg.MessageLevel;
-
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-
-/**
- * User: serso
- * Date: 1/20/13
- * Time: 12:47 PM
- */
-public interface DialogData {
-
-    @Nonnull
-    String getMessage();
-
-    @Nonnull
-    MessageLevel getMessageLevel();
-
-    @Nullable
-    String getTitle();
-}
diff --git a/app/src/main/java/org/solovyev/android/calculator/MessageDialogData.java b/app/src/main/java/org/solovyev/android/calculator/MessageDialogData.java
deleted file mode 100644
index ec66d4cd..00000000
--- a/app/src/main/java/org/solovyev/android/calculator/MessageDialogData.java
+++ /dev/null
@@ -1,71 +0,0 @@
-/*
- * 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
- */
-
-package org.solovyev.android.calculator;
-
-import org.solovyev.common.msg.Message;
-import org.solovyev.common.msg.MessageLevel;
-
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-
-/**
- * User: serso
- * Date: 1/20/13
- * Time: 12:45 PM
- */
-public class MessageDialogData implements DialogData {
-
-    @Nonnull
-    private Message message;
-
-    @Nullable
-    private String title;
-
-    private MessageDialogData(@Nonnull Message message, @Nullable String title) {
-        this.message = message;
-        this.title = title;
-    }
-
-    @Nonnull
-    public static DialogData newInstance(@Nonnull Message message, @Nullable String title) {
-        return new MessageDialogData(message, title);
-    }
-
-    @Override
-    @Nonnull
-    public String getMessage() {
-        return message.getLocalizedMessage();
-    }
-
-    @Nonnull
-    @Override
-    public MessageLevel getMessageLevel() {
-        return message.getMessageLevel();
-    }
-
-    @Override
-    @Nullable
-    public String getTitle() {
-        return title;
-    }
-}
diff --git a/app/src/main/java/org/solovyev/android/calculator/ParcelableDialogData.java b/app/src/main/java/org/solovyev/android/calculator/ParcelableDialogData.java
deleted file mode 100644
index 4206ad22..00000000
--- a/app/src/main/java/org/solovyev/android/calculator/ParcelableDialogData.java
+++ /dev/null
@@ -1,130 +0,0 @@
-/*
- * 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
- */
-
-package org.solovyev.android.calculator;
-
-import android.os.Parcel;
-import android.os.Parcelable;
-
-import org.solovyev.common.msg.MessageLevel;
-import org.solovyev.common.msg.MessageType;
-
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-
-/**
- * User: serso
- * Date: 1/20/13
- * Time: 1:04 PM
- */
-public final class ParcelableDialogData implements DialogData, Parcelable {
-
-	/*
-    **********************************************************************
-	*
-	*                           STATIC
-	*
-	**********************************************************************
-	*/
-
-    public final static Creator<ParcelableDialogData> CREATOR = new Creator<ParcelableDialogData>() {
-        @Override
-        public ParcelableDialogData createFromParcel(@Nonnull Parcel in) {
-            return fromParcel(in);
-        }
-
-        @Override
-        public ParcelableDialogData[] newArray(int size) {
-            return new ParcelableDialogData[size];
-        }
-    };
-
-	/*
-	**********************************************************************
-	*
-	*                           FIELDS
-	*
-	**********************************************************************
-	*/
-
-    @Nonnull
-    private DialogData nestedData;
-
-	/*
-	**********************************************************************
-	*
-	*                           CONSTRUCTORS
-	*
-	**********************************************************************
-	*/
-
-    public ParcelableDialogData(@Nonnull DialogData nestedData) {
-        this.nestedData = nestedData;
-    }
-
-    @Nonnull
-    public static ParcelableDialogData wrap(@Nonnull DialogData nestedData) {
-        if (nestedData instanceof ParcelableDialogData) {
-            return ((ParcelableDialogData) nestedData);
-        } else {
-            return new ParcelableDialogData(nestedData);
-        }
-    }
-
-    @Nonnull
-    public static ParcelableDialogData fromParcel(@Nonnull Parcel in) {
-        final String message = in.readString();
-        final MessageType messageType = CalculatorMessages.toMessageType(in.readInt());
-        final String title = in.readString();
-        return wrap(StringDialogData.newInstance(message, messageType, title));
-    }
-
-    @Nonnull
-    @Override
-    public String getMessage() {
-        return nestedData.getMessage();
-    }
-
-    @Nonnull
-    @Override
-    public MessageLevel getMessageLevel() {
-        return nestedData.getMessageLevel();
-    }
-
-    @Nullable
-    @Override
-    public String getTitle() {
-        return nestedData.getTitle();
-    }
-
-    @Override
-    public int describeContents() {
-        return 0;
-    }
-
-    @Override
-    public void writeToParcel(@Nonnull Parcel out, int flags) {
-        out.writeString(this.getMessage());
-        out.writeInt(this.getMessageLevel().getMessageLevel());
-        out.writeString(this.getTitle());
-    }
-}
diff --git a/app/src/main/java/org/solovyev/android/calculator/StringDialogData.java b/app/src/main/java/org/solovyev/android/calculator/StringDialogData.java
deleted file mode 100644
index e8d6d3a2..00000000
--- a/app/src/main/java/org/solovyev/android/calculator/StringDialogData.java
+++ /dev/null
@@ -1,74 +0,0 @@
-/*
- * 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
- */
-
-package org.solovyev.android.calculator;
-
-import org.solovyev.common.msg.MessageType;
-
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-
-/**
- * User: serso
- * Date: 1/20/13
- * Time: 1:01 PM
- */
-public class StringDialogData implements DialogData {
-
-    @Nonnull
-    private final String message;
-
-    @Nonnull
-    private final MessageType messageType;
-
-    @Nullable
-    private final String title;
-
-    private StringDialogData(@Nonnull String message, @Nonnull MessageType messageType, @Nullable String title) {
-        this.message = message;
-        this.messageType = messageType;
-        this.title = title;
-    }
-
-    @Nonnull
-    public static DialogData newInstance(@Nonnull String message, @Nonnull MessageType messageType, @Nullable String title) {
-        return new StringDialogData(message, messageType, title);
-    }
-
-    @Nonnull
-    @Override
-    public String getMessage() {
-        return message;
-    }
-
-    @Nonnull
-    @Override
-    public MessageType getMessageLevel() {
-        return messageType;
-    }
-
-    @Nullable
-    @Override
-    public String getTitle() {
-        return title;
-    }
-}
diff --git a/app/src/test/java/org/solovyev/android/calculator/CalculatorTestUtils.java b/app/src/test/java/org/solovyev/android/calculator/CalculatorTestUtils.java
index 8a2019ce..61290c0e 100644
--- a/app/src/test/java/org/solovyev/android/calculator/CalculatorTestUtils.java
+++ b/app/src/test/java/org/solovyev/android/calculator/CalculatorTestUtils.java
@@ -23,9 +23,8 @@
 package org.solovyev.android.calculator;
 
 import android.content.Context;
-
 import com.squareup.otto.Bus;
-
+import jscl.JsclMathEngine;
 import org.junit.Assert;
 import org.mockito.Mockito;
 import org.robolectric.fakes.RoboSharedPreferences;
@@ -36,12 +35,9 @@ import org.solovyev.android.calculator.operators.OperatorsRegistry;
 import org.solovyev.android.calculator.operators.PostfixFunctionsRegistry;
 import org.solovyev.android.calculator.plot.CalculatorPlotter;
 
-import java.io.ByteArrayInputStream;
-import java.io.ByteArrayOutputStream;
-import java.io.IOException;
-import java.io.ObjectInputStream;
-import java.io.ObjectOutputStream;
-import java.io.Serializable;
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import java.io.*;
 import java.text.DecimalFormatSymbols;
 import java.util.HashMap;
 import java.util.Map;
@@ -49,11 +45,6 @@ import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
 
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-
-import jscl.JsclMathEngine;
-
 /**
  * User: serso
  * Date: 10/7/12
@@ -105,8 +96,8 @@ public class CalculatorTestUtils {
 
         final VariablesRegistry variablesRegistry = new VariablesRegistry(jsclEngine);
         final FunctionsRegistry functionsRegistry = new FunctionsRegistry(jsclEngine);
-        final OperatorsRegistry operatorsRegistry = new OperatorsRegistry(jsclEngine.getOperatorsRegistry());
-        final PostfixFunctionsRegistry postfixFunctionsRegistry = new PostfixFunctionsRegistry(jsclEngine.getPostfixFunctionsRegistry());
+        final OperatorsRegistry operatorsRegistry = new OperatorsRegistry(jsclEngine);
+        final PostfixFunctionsRegistry postfixFunctionsRegistry = new PostfixFunctionsRegistry(jsclEngine);
 
         return new Engine(jsclEngine, variablesRegistry, functionsRegistry, operatorsRegistry, postfixFunctionsRegistry);
     }