diff --git a/app/build.gradle b/app/build.gradle
index 9aae5e8b..d02de8d6 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -83,6 +83,7 @@ dependencies {
     compile(name: 'plotter', ext: 'aar')
     compile 'com.google.guava:guava:19.0'
     compile('org.simpleframework:simple-xml:2.6.1') {
+        exclude(module: 'stax')
         exclude(module: 'stax-api')
         exclude(module: 'xpp3')
     }
diff --git a/app/src/androidTest/java/net/slideshare/mobile/test/util/OrientationChangeAction.java b/app/src/androidTest/java/net/slideshare/mobile/test/util/OrientationChangeAction.java
index 2aa70ee5..47c4cc98 100644
--- a/app/src/androidTest/java/net/slideshare/mobile/test/util/OrientationChangeAction.java
+++ b/app/src/androidTest/java/net/slideshare/mobile/test/util/OrientationChangeAction.java
@@ -24,6 +24,7 @@
  */
 package net.slideshare.mobile.test.util;
 
+import android.annotation.SuppressLint;
 import android.app.Activity;
 import android.content.pm.ActivityInfo;
 import android.support.test.espresso.UiController;
@@ -60,8 +61,7 @@ public class OrientationChangeAction implements ViewAction {
     @Override
     public void perform(UiController uiController, View view) {
         uiController.loopMainThreadUntilIdle();
-        final Activity activity = (Activity) view.getContext();
-        activity.setRequestedOrientation(orientation);
+        requestOrientation(view);
 
         Collection<Activity> resumedActivities = ActivityLifecycleMonitorRegistry.getInstance().getActivitiesInStage(Stage.RESUMED);
         if (resumedActivities.isEmpty()) {
@@ -69,6 +69,12 @@ public class OrientationChangeAction implements ViewAction {
         }
     }
 
+    @SuppressLint("WrongConstant")
+    private void requestOrientation(View view) {
+        final Activity activity = (Activity) view.getContext();
+        activity.setRequestedOrientation(orientation);
+    }
+
     public static ViewAction orientationLandscape() {
         return new OrientationChangeAction(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
     }
diff --git a/app/src/main/java/org/solovyev/android/calculator/DisplayFragment.java b/app/src/main/java/org/solovyev/android/calculator/DisplayFragment.java
index 1c9b4898..32a3a35b 100644
--- a/app/src/main/java/org/solovyev/android/calculator/DisplayFragment.java
+++ b/app/src/main/java/org/solovyev/android/calculator/DisplayFragment.java
@@ -22,7 +22,6 @@
 
 package org.solovyev.android.calculator;
 
-import android.app.Activity;
 import android.content.Context;
 import android.content.SharedPreferences;
 import android.os.Bundle;
@@ -31,7 +30,6 @@ import android.support.annotation.Nullable;
 import android.support.annotation.StringRes;
 import android.support.v7.app.AlertDialog;
 import android.view.*;
-import android.widget.TextView;
 import butterknife.Bind;
 import butterknife.ButterKnife;
 import com.squareup.otto.Bus;
@@ -172,20 +170,10 @@ public class DisplayFragment extends BaseFragment implements View.OnClickListene
     }
 
     public static void showEvaluationError(@Nonnull Context context,
-            @Nonnull final String errorMessage) {
-        final LayoutInflater layoutInflater =
-                (LayoutInflater) context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
-
-        final View errorMessageView = layoutInflater.inflate(R.layout.display_error_message, null);
-        ((TextView) errorMessageView.findViewById(R.id.error_message_text_view))
-                .setText(errorMessage);
-
-        final AlertDialog.Builder builder =
-                new AlertDialog.Builder(context, App.getTheme().alertDialogTheme)
-                        .setPositiveButton(R.string.cpp_cancel, null)
-                        .setView(errorMessageView);
-
-        builder.create().show();
+                                           @Nonnull final String errorMessage) {
+        new AlertDialog.Builder(context, App.getTheme().alertDialogTheme)
+                .setPositiveButton(R.string.cpp_cancel, null)
+                .setMessage(errorMessage).create().show();
     }
 
     @Override
diff --git a/app/src/main/java/org/solovyev/android/calculator/plot/ExpressionFunction.java b/app/src/main/java/org/solovyev/android/calculator/plot/ExpressionFunction.java
index acdefc26..377560ac 100644
--- a/app/src/main/java/org/solovyev/android/calculator/plot/ExpressionFunction.java
+++ b/app/src/main/java/org/solovyev/android/calculator/plot/ExpressionFunction.java
@@ -38,7 +38,7 @@ public class ExpressionFunction extends Function {
                 name = function.toString();
             }
             if (name.length() > 10) {
-                name = name.substring(0, 10) + "...";
+                name = name.substring(0, 10) + "…";
             }
         }
         return imaginary ? "Im(" + name + ")" : name;
diff --git a/app/src/main/java/org/solovyev/android/prefs/CollectionSetPreference.java b/app/src/main/java/org/solovyev/android/prefs/CollectionSetPreference.java
deleted file mode 100644
index 2dbd52ad..00000000
--- a/app/src/main/java/org/solovyev/android/prefs/CollectionSetPreference.java
+++ /dev/null
@@ -1,68 +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.prefs;
-
-import android.content.SharedPreferences;
-import org.solovyev.common.text.Mapper;
-
-import javax.annotation.Nonnull;
-import java.util.Collection;
-import java.util.HashSet;
-import java.util.Set;
-
-public abstract class CollectionSetPreference<C extends Collection<T>, T> extends AbstractPreference<C> {
-
-    @Nonnull
-    private final Mapper<T> mapper;
-
-    protected CollectionSetPreference(@Nonnull String id, @Nonnull C defaultValue, @Nonnull Mapper<T> mapper) {
-        super(id, defaultValue);
-        this.mapper = mapper;
-    }
-
-    @Override
-    protected C getPersistedValue(@Nonnull SharedPreferences preferences) {
-        final Set<String> stringValues = preferences.getStringSet(getKey(), null);
-
-        final C result = createCollection(stringValues.size());
-        for (String stringValue : stringValues) {
-            result.add(mapper.parseValue(stringValue));
-        }
-
-        return result;
-    }
-
-    @Nonnull
-    protected abstract C createCollection(int size);
-
-    @Override
-    protected void putPersistedValue(@Nonnull SharedPreferences.Editor editor, @Nonnull C values) {
-
-        final Set<String> result = new HashSet<String>(values.size());
-        for (T value : values) {
-            result.add(mapper.formatValue(value));
-        }
-
-        editor.putStringSet(getKey(), result);
-    }
-}
diff --git a/app/src/main/java/org/solovyev/android/prefs/HashSetPreference.java b/app/src/main/java/org/solovyev/android/prefs/HashSetPreference.java
deleted file mode 100644
index bba8a5d1..00000000
--- a/app/src/main/java/org/solovyev/android/prefs/HashSetPreference.java
+++ /dev/null
@@ -1,59 +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.prefs;
-
-import org.solovyev.common.text.EnumMapper;
-import org.solovyev.common.text.Mapper;
-import org.solovyev.common.text.StringMapper;
-
-import javax.annotation.Nonnull;
-import java.util.HashSet;
-import java.util.Set;
-
-public class HashSetPreference<T> extends CollectionSetPreference<Set<T>, T> {
-
-    private HashSetPreference(@Nonnull String id, @Nonnull Set<T> defaultValue, @Nonnull Mapper<T> mapper) {
-        super(id, defaultValue, mapper);
-    }
-
-    @Nonnull
-    public static HashSetPreference<String> ofStrings(@Nonnull String key, @Nonnull Set<String> defaultValue) {
-        return new HashSetPreference<String>(key, defaultValue, StringMapper.getInstance());
-    }
-
-    @Nonnull
-    public static <T> HashSetPreference<T> ofTypedValues(@Nonnull String key, @Nonnull Set<T> defaultValue, @Nonnull Mapper<T> parser) {
-        return new HashSetPreference<T>(key, defaultValue, parser);
-    }
-
-    @Nonnull
-    public static <T extends Enum> HashSetPreference<T> ofEnums(@Nonnull String id, @Nonnull Set<T> defaultValue, @Nonnull Class<T> enumType) {
-        return new HashSetPreference<T>(id, defaultValue, EnumMapper.of(enumType));
-    }
-
-    @Nonnull
-    @Override
-    protected Set<T> createCollection(int size) {
-        return new HashSet<T>(size);
-    }
-}
diff --git a/app/src/main/res/drawable-hdpi/ab_clock.png b/app/src/main/res/drawable-hdpi/ab_clock.png
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index 96910bfb..00000000
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diff --git a/app/src/main/res/drawable-xxxhdpi/ab_logo.png b/app/src/main/res/drawable-xxxhdpi/ab_logo.png
deleted file mode 100644
index 9e8f92af..00000000
Binary files a/app/src/main/res/drawable-xxxhdpi/ab_logo.png and /dev/null differ
diff --git a/app/src/main/res/drawable-xxxhdpi/ic_file_download_white_24dp.png b/app/src/main/res/drawable-xxxhdpi/ic_file_download_white_24dp.png
deleted file mode 100644
index ded5652e..00000000
Binary files a/app/src/main/res/drawable-xxxhdpi/ic_file_download_white_24dp.png and /dev/null differ
diff --git a/app/src/main/res/drawable-xxxhdpi/ic_space_bar_white_24dp.png b/app/src/main/res/drawable-xxxhdpi/ic_space_bar_white_24dp.png
deleted file mode 100644
index 1798cb96..00000000
Binary files a/app/src/main/res/drawable-xxxhdpi/ic_space_bar_white_24dp.png and /dev/null differ
diff --git a/app/src/main/res/layout/cpp_dialog.xml b/app/src/main/res/layout/cpp_dialog.xml
deleted file mode 100644
index a9f7eae8..00000000
--- a/app/src/main/res/layout/cpp_dialog.xml
+++ /dev/null
@@ -1,31 +0,0 @@
-<?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
-  -->
-
-<LinearLayout
-    xmlns:a="http://schemas.android.com/apk/res/android"
-    a:id="@+id/dialog_layout"
-    style="@style/CppDialog"
-    a:orientation="vertical">
-
-</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_dialog_fragment.xml b/app/src/main/res/layout/cpp_dialog_fragment.xml
deleted file mode 100644
index 184b745e..00000000
--- a/app/src/main/res/layout/cpp_dialog_fragment.xml
+++ /dev/null
@@ -1,63 +0,0 @@
-<?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
-  -->
-
-<LinearLayout
-    xmlns:a="http://schemas.android.com/apk/res/android"
-    a:id="@+id/main_fragment_layout"
-    style="@style/CppFragment"
-    a:layout_width="match_parent"
-    a:layout_height="match_parent"
-    a:layout_gravity="center_horizontal"
-    a:orientation="vertical">
-
-    <TextView
-        a:id="@+id/cpp_dialog_message_textview"
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:maxLines="10"
-        a:scrollbars="vertical" />
-
-    <LinearLayout
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:orientation="horizontal">
-
-        <Button
-            a:id="@+id/cpp_copy_button"
-            a:layout_width="0dp"
-            a:layout_height="wrap_content"
-            a:layout_weight="1"
-            a:text="@string/c_copy"
-            a:visibility="gone" />
-
-        <Button
-            a:id="@+id/cpp_ok_button"
-            a:layout_width="0dp"
-            a:layout_height="wrap_content"
-            a:layout_weight="1"
-            a:text="@string/ok" />
-
-    </LinearLayout>
-
-</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_fixable_messages_dialog.xml b/app/src/main/res/layout/cpp_fixable_messages_dialog.xml
deleted file mode 100644
index 6f814a66..00000000
--- a/app/src/main/res/layout/cpp_fixable_messages_dialog.xml
+++ /dev/null
@@ -1,55 +0,0 @@
-<?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
-  -->
-
-<LinearLayout
-    xmlns:a="http://schemas.android.com/apk/res/android"
-    style="@style/CppDialog">
-
-    <LinearLayout
-        a:id="@+id/cpp_fixable_messages_container"
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:orientation="vertical" />
-
-    <CheckBox
-        a:id="@+id/cpp_do_not_show_fixable_messages_checkbox"
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:text="@string/do_not_show_messages_in_session" />
-
-    <LinearLayout
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:gravity="center"
-        a:orientation="horizontal">
-
-        <Button
-            a:id="@+id/close_button"
-            a:layout_width="wrap_content"
-            a:layout_height="wrap_content"
-            a:text="@string/close" />
-
-    </LinearLayout>
-
-</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_fixable_messages_dialog_message.xml b/app/src/main/res/layout/cpp_fixable_messages_dialog_message.xml
deleted file mode 100644
index 1f901c47..00000000
--- a/app/src/main/res/layout/cpp_fixable_messages_dialog_message.xml
+++ /dev/null
@@ -1,46 +0,0 @@
-<?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
-  -->
-
-<LinearLayout xmlns:a="http://schemas.android.com/apk/res/android"
-    a:layout_width="match_parent"
-    a:layout_height="wrap_content"
-    a:orientation="horizontal"
-    a:padding="6dp">
-
-    <TextView
-        a:id="@+id/cpp_fixable_messages_text_view"
-        a:layout_width="0dp"
-        a:layout_height="wrap_content"
-        a:layout_gravity="fill"
-        a:layout_weight="5"
-        a:text="@+id/cpp_fixable_messages_text_view" />
-
-    <Button
-        a:id="@+id/cpp_fix_button"
-        a:layout_width="0dp"
-        a:layout_height="wrap_content"
-        a:layout_weight="2"
-        a:text="@string/fix" />
-
-</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_plot_fragment.xml b/app/src/main/res/layout/cpp_plot_fragment.xml
deleted file mode 100644
index acc73f65..00000000
--- a/app/src/main/res/layout/cpp_plot_fragment.xml
+++ /dev/null
@@ -1,34 +0,0 @@
-<?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
-  -->
-
-<LinearLayout
-    xmlns:a="http://schemas.android.com/apk/res/android"
-    a:id="@+id/main_fragment_layout"
-    style="@style/CppFragment"
-    a:layout_width="match_parent"
-    a:layout_height="match_parent">
-
-    <org.solovyev.android.calculator.AdView style="@style/CppAd" />
-
-</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_plot_function_list_item.xml b/app/src/main/res/layout/cpp_plot_function_list_item.xml
deleted file mode 100644
index 0339188f..00000000
--- a/app/src/main/res/layout/cpp_plot_function_list_item.xml
+++ /dev/null
@@ -1,58 +0,0 @@
-<?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
-  -->
-
-<LinearLayout xmlns:a="http://schemas.android.com/apk/res/android"
-    a:layout_width="match_parent"
-    a:layout_height="wrap_content"
-    a:orientation="horizontal">
-
-    <TextView
-        a:id="@+id/cpp_plot_function_expression_textview"
-        a:layout_width="0dp"
-        a:layout_height="wrap_content"
-        a:layout_weight="3" />
-
-    <CheckBox
-        a:id="@+id/cpp_plot_function_pinned_checkbox"
-        a:layout_width="0dp"
-        a:layout_height="wrap_content"
-        a:layout_weight="1" />
-
-    <CheckBox
-        a:id="@+id/cpp_plot_function_visible_checkbox"
-        a:layout_width="0dp"
-        a:layout_height="wrap_content"
-        a:layout_weight="1" />
-
-    <ImageButton
-        a:id="@+id/cpp_plot_function_settings_button"
-        a:layout_width="0dp"
-        a:layout_height="wrap_content"
-        a:layout_weight="1"
-        a:paddingBottom="0dp"
-        a:paddingTop="0dp"
-        a:scaleType="centerInside"
-        a:src="@drawable/ic_settings_white_48dp" />
-
-</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_plot_function_settings_dialog.xml b/app/src/main/res/layout/cpp_plot_function_settings_dialog.xml
deleted file mode 100644
index eb006dbb..00000000
--- a/app/src/main/res/layout/cpp_plot_function_settings_dialog.xml
+++ /dev/null
@@ -1,30 +0,0 @@
-<?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
-  -->
-
-<LinearLayout
-    xmlns:a="http://schemas.android.com/apk/res/android"
-    a:id="@+id/dialog_layout"
-    style="@style/CppDialog">
-
-</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_plot_function_settings_fragment.xml b/app/src/main/res/layout/cpp_plot_function_settings_fragment.xml
deleted file mode 100644
index 50a524a5..00000000
--- a/app/src/main/res/layout/cpp_plot_function_settings_fragment.xml
+++ /dev/null
@@ -1,85 +0,0 @@
-<?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
-  -->
-
-<LinearLayout
-    xmlns:a="http://schemas.android.com/apk/res/android"
-    a:id="@+id/main_fragment_layout"
-    style="@style/CppFragment"
-    a:layout_width="wrap_content"
-    a:layout_height="match_parent"
-    a:layout_gravity="center_horizontal"
-    a:orientation="vertical">
-
-    <org.solovyev.android.calculator.AdView style="@style/CppAd" />
-
-    <TextView
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:text="@string/cpp_plot_function_line_color_type" />
-
-    <Spinner
-        a:id="@+id/cpp_plot_function_line_color_type_spinner"
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:entries="@array/cpp_plot_line_color_type_names" />
-
-    <TextView
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:text="@string/cpp_plot_function_line_color" />
-
-    <Spinner
-        a:id="@+id/cpp_plot_function_line_color_spinner"
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:entries="@array/cpp_plot_line_color_names" />
-
-    <TextView
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:text="@string/cpp_plot_function_line_style" />
-
-    <Spinner
-        a:id="@+id/cpp_plot_function_line_style_spinner"
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:entries="@array/cpp_plot_line_style_names" />
-
-    <TextView
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:text="@string/cpp_plot_function_line_width" />
-
-    <SeekBar
-        a:id="@+id/cpp_plot_functions_line_width_seekbar"
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content" />
-
-    <Button
-        a:id="@+id/cpp_apply_button"
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:text="@string/cpp_apply" />
-
-</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_plot_functions_fragment.xml b/app/src/main/res/layout/cpp_plot_functions_fragment.xml
deleted file mode 100644
index 966d6343..00000000
--- a/app/src/main/res/layout/cpp_plot_functions_fragment.xml
+++ /dev/null
@@ -1,66 +0,0 @@
-<?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
-  -->
-
-<LinearLayout
-    xmlns:a="http://schemas.android.com/apk/res/android"
-    a:id="@+id/main_fragment_layout"
-    style="@style/CppFragment"
-    a:layout_width="match_parent"
-    a:layout_height="match_parent">
-
-    <org.solovyev.android.calculator.AdView style="@style/CppAd" />
-
-    <LinearLayout
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:orientation="horizontal">
-
-        <TextView
-            a:layout_width="0dp"
-            a:layout_height="wrap_content"
-            a:layout_weight="3"
-            a:text="@string/cpp_function" />
-
-        <TextView
-            a:layout_width="0dp"
-            a:layout_height="wrap_content"
-            a:layout_weight="1"
-            a:text="@string/cpp_pinned" />
-
-        <TextView
-            a:layout_width="0dp"
-            a:layout_height="wrap_content"
-            a:layout_weight="1"
-            a:text="@string/cpp_visible" />
-
-        <TextView
-            a:layout_width="0dp"
-            a:layout_height="wrap_content"
-            a:layout_weight="1" />
-
-    </LinearLayout>
-
-    <ListView style="@style/CppListView" />
-
-</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_plot_range_fragment.xml b/app/src/main/res/layout/cpp_plot_range_fragment.xml
deleted file mode 100644
index b2121afa..00000000
--- a/app/src/main/res/layout/cpp_plot_range_fragment.xml
+++ /dev/null
@@ -1,132 +0,0 @@
-<?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
-  -->
-
-<LinearLayout
-    xmlns:a="http://schemas.android.com/apk/res/android"
-    a:id="@+id/main_fragment_layout"
-    style="@style/CppFragment"
-    a:layout_width="match_parent"
-    a:layout_height="match_parent"
-    a:layout_gravity="center_horizontal"
-    a:orientation="vertical">
-
-    <org.solovyev.android.calculator.AdView style="@style/CppAd" />
-
-    <LinearLayout
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:baselineAligned="false"
-        a:orientation="horizontal">
-
-        <LinearLayout
-            a:layout_width="0dp"
-            a:layout_height="wrap_content"
-            a:layout_weight="1"
-            a:orientation="vertical">
-
-            <TextView
-                a:layout_width="match_parent"
-                a:layout_height="wrap_content"
-                a:text="@string/cpp_plot_range_x_min" />
-
-            <EditText
-                a:id="@+id/cpp_plot_range_x_min_editext"
-                a:layout_width="match_parent"
-                a:layout_height="wrap_content"
-                a:inputType="numberDecimal|numberSigned" />
-        </LinearLayout>
-
-        <LinearLayout
-            a:layout_width="0dp"
-            a:layout_height="wrap_content"
-            a:layout_weight="1"
-            a:orientation="vertical">
-
-            <TextView
-                a:layout_width="match_parent"
-                a:layout_height="wrap_content"
-                a:text="@string/cpp_plot_range_x_max" />
-
-            <EditText
-                a:id="@+id/cpp_plot_range_x_max_editext"
-                a:layout_width="match_parent"
-                a:layout_height="wrap_content"
-                a:inputType="numberDecimal|numberSigned" />
-        </LinearLayout>
-
-
-    </LinearLayout>
-
-    <LinearLayout
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:baselineAligned="false"
-        a:orientation="horizontal">
-
-        <LinearLayout
-            a:layout_width="0dp"
-            a:layout_height="wrap_content"
-            a:layout_weight="1"
-            a:orientation="vertical">
-
-            <TextView
-                a:layout_width="match_parent"
-                a:layout_height="wrap_content"
-                a:text="@string/cpp_plot_range_y_min" />
-
-            <EditText
-                a:id="@+id/cpp_plot_range_y_min_editext"
-                a:layout_width="match_parent"
-                a:layout_height="wrap_content"
-                a:inputType="numberDecimal|numberSigned" />
-        </LinearLayout>
-
-        <LinearLayout
-            a:layout_width="0dp"
-            a:layout_height="wrap_content"
-            a:layout_weight="1"
-            a:orientation="vertical">
-
-            <TextView
-                a:layout_width="match_parent"
-                a:layout_height="wrap_content"
-                a:text="@string/cpp_plot_range_y_max" />
-
-            <EditText
-                a:id="@+id/cpp_plot_range_y_max_editext"
-                a:layout_width="match_parent"
-                a:layout_height="wrap_content"
-                a:inputType="numberDecimal|numberSigned" />
-        </LinearLayout>
-
-
-    </LinearLayout>
-
-    <Button
-        a:id="@+id/cpp_apply_button"
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:text="@string/cpp_apply" />
-
-</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/cpp_plotter_fragment.xml b/app/src/main/res/layout/cpp_plotter_fragment.xml
deleted file mode 100644
index dc74f392..00000000
--- a/app/src/main/res/layout/cpp_plotter_fragment.xml
+++ /dev/null
@@ -1,72 +0,0 @@
-<?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
-  -->
-
-<LinearLayout
-    xmlns:a="http://schemas.android.com/apk/res/android"
-    a:id="@+id/main_fragment_layout"
-    style="@style/CppFragment"
-    a:layout_width="match_parent"
-    a:layout_height="match_parent">
-
-    <org.solovyev.android.calculator.AdView style="@style/CppAd" />
-
-    <org.solovyev.android.plotter.PlotView
-        a:id="@+id/plotview"
-        a:layout_width="match_parent"
-        a:layout_height="0dp"
-        a:layout_weight="1" />
-
-    <LinearLayout
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:background="@android:color/black"
-        a:gravity="center"
-        a:orientation="horizontal">
-
-        <Button
-            a:id="@+id/zoom_out_button"
-            a:layout_width="wrap_content"
-            a:layout_height="wrap_content"
-            a:text="-" />
-
-        <Button
-            a:id="@+id/zoom_0_button"
-            a:layout_width="wrap_content"
-            a:layout_height="wrap_content"
-            a:text="0" />
-
-        <Button
-            a:id="@+id/zoom_in_button"
-            a:layout_width="wrap_content"
-            a:layout_height="wrap_content"
-            a:text="+" />
-
-        <Button
-            a:id="@+id/plot_mode_button"
-            a:layout_width="wrap_content"
-            a:layout_height="wrap_content"
-            a:text="2D/3D" />
-    </LinearLayout>
-
-</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/display_error_message.xml b/app/src/main/res/layout/display_error_message.xml
deleted file mode 100644
index 7cc7d6b3..00000000
--- a/app/src/main/res/layout/display_error_message.xml
+++ /dev/null
@@ -1,46 +0,0 @@
-<?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
-  -->
-
-<ScrollView xmlns:a="http://schemas.android.com/apk/res/android"
-    a:layout_width="fill_parent"
-    a:layout_height="fill_parent">
-
-    <LinearLayout
-        a:layout_width="match_parent"
-        a:layout_height="wrap_content"
-        a:orientation="vertical"
-        a:scrollbarAlwaysDrawVerticalTrack="true"
-        a:scrollbars="vertical">
-
-        <TextView
-            a:id="@+id/error_message_text_view"
-            style="@style/cpp_default_text_size"
-            a:layout_width="wrap_content"
-            a:layout_height="fill_parent"
-            a:padding="6dp" />
-
-    </LinearLayout>
-
-</ScrollView>
-
diff --git a/app/src/main/res/values-ar/text_strings.xml b/app/src/main/res/values-ar/text_strings.xml
index ee4f6854..993d8040 100644
--- a/app/src/main/res/values-ar/text_strings.xml
+++ b/app/src/main/res/values-ar/text_strings.xml
@@ -153,7 +153,6 @@
     <string name="function_name_is_not_valid">اسم الدالّة غير صالح: الاسم يجب أن يبدأ بحرف, ويمكن أن تحتوي على أحرف, أرقام وإشارة _.</string>
     <string name="function_already_exists">هناك دالّة بنفس الاسم موجود مسبقاً!</string>
     <string name="function_is_empty">لا يمكن أن يكون نص الدالّة فارغة!</string>
-    <string name="function_param_not_empty">لا ينبغي أن يكون العامل المتغير في الدالة فارغاً!</string>
     <string name="function_removal_confirmation_question">هل تريد حقاً حذف الدالة \'%s\'؟</string>
     <string name="empty_function_error">غير قادر على إنشاء دالّة فارغة!</string>
     <string name="do_not_show_messages_in_session">عدم إظهار هذه الرسالة حتى الدورة القادمة</string>
diff --git a/app/src/main/res/values-cs/text_strings.xml b/app/src/main/res/values-cs/text_strings.xml
index c5665810..a19fa8fb 100644
--- a/app/src/main/res/values-cs/text_strings.xml
+++ b/app/src/main/res/values-cs/text_strings.xml
@@ -154,7 +154,6 @@ Google Play</a>,\n nechte komentář nebo \ndiskutujte o aplikaci \nna
     <string name="function_name_is_not_valid">Název funkce není platný: jméno musí začínat písmenem, může obsahovat písmena, číslice a podtržítka!</string>
     <string name="function_already_exists">Funkce se stejným názvem již existuje!</string>
     <string name="function_is_empty">Tělo funkce nemůže být prázdné!</string>
-    <string name="function_param_not_empty">Parametr funkce nemůže být prázdný</string>
     <string name="function_removal_confirmation_question">Opravdu chcete odstranit \'%s\' funkci?</string>
     <string name="empty_function_error">Nelze vytvořit prázdnou funkci!</string>
     <string name="do_not_show_messages_in_session">Nezobrazovat tuto zprávu až do příštího spuštění</string>
diff --git a/app/src/main/res/values-de/text_strings.xml b/app/src/main/res/values-de/text_strings.xml
index 07b4ecb8..315b544e 100644
--- a/app/src/main/res/values-de/text_strings.xml
+++ b/app/src/main/res/values-de/text_strings.xml
@@ -152,7 +152,6 @@ Google Play</a>,\nschreiben Sie einen Kommentar oder\ndiskutieren Sie die Anwend
     <string name="function_name_is_not_valid">Name der Funktion ist ungültig: Name muss mit einem Buchstaben beginnen und darf Buchstaben, Ziffern und Unterstriche enthalten.</string>
     <string name="function_already_exists">Funktion mit demselben Namen existiert bereits!</string>
     <string name="function_is_empty">Funktion darf nicht leer sein!</string>
-    <string name="function_param_not_empty">Funktionsparameter sollte nicht leer sein!</string>
     <string name="function_removal_confirmation_question">Möchten Sie die Funktion \'%s\' wirklich löschen?</string>
     <string name="empty_function_error">Eine leere Funktion kann nicht erstellt werden!</string>
     <string name="do_not_show_messages_in_session">Diese Nachricht bis zum nächsten Mal verbergen</string>
diff --git a/app/src/main/res/values-es/text_strings.xml b/app/src/main/res/values-es/text_strings.xml
index ae761c34..cdc6c1a1 100644
--- a/app/src/main/res/values-es/text_strings.xml
+++ b/app/src/main/res/values-es/text_strings.xml
@@ -152,7 +152,6 @@
     <string name="function_name_is_not_valid">El nombre de la función no es válido: El nombre debe comenzar con una letra, y puede contener letras, dígitos y líneas.</string>
     <string name="function_already_exists">¡Ya existe una función con el mismo nombre!</string>
     <string name="function_is_empty">¡El cuerpo de la función no puede estar vacío!</string>
-    <string name="function_param_not_empty">¡El parámetro de la función no puede estar vacío!</string>
     <string name="function_removal_confirmation_question">¿Estás seguro de que quieres eliminar la función \'%s\'?</string>
     <string name="empty_function_error">¡No se puede crear una función vacía!</string>
     <string name="do_not_show_messages_in_session">No mostrar este mensaje hasta la próxima sesión</string>
diff --git a/app/src/main/res/values-fi/text_strings.xml b/app/src/main/res/values-fi/text_strings.xml
index 45b52d4d..bc43848e 100644
--- a/app/src/main/res/values-fi/text_strings.xml
+++ b/app/src/main/res/values-fi/text_strings.xml
@@ -149,7 +149,6 @@
     <string name="function_name_is_not_valid">Toiminnon nimi ei kelpaa: nimen on alettava kirjaimella, voi sisältää kirjaimia, numeroita ja alaviivoja.  </string>
     <string name="function_already_exists">Saman niminen toiminto on jo olemassa!</string>
     <string name="function_is_empty">Toiminnon elin ei voi olla tyhjä!</string>
-    <string name="function_param_not_empty">Funktioparametri ei pitäisi olla tyhjä!</string>
     <string name="function_removal_confirmation_question">Haluatko todella poistaa toiminnon \'%s\'?</string>
     <string name="empty_function_error">Tyhjä funktion luominen ei onnistunut.</string>
     <string name="do_not_show_messages_in_session">Älä näytä tätä viestiä kunnes seuraavan istunnon</string>
diff --git a/app/src/main/res/values-fr/text_strings.xml b/app/src/main/res/values-fr/text_strings.xml
index 3d6622d2..17a517bd 100644
--- a/app/src/main/res/values-fr/text_strings.xml
+++ b/app/src/main/res/values-fr/text_strings.xml
@@ -149,7 +149,6 @@
     <string name="function_name_is_not_valid">Nom de fonction invalide : le nom doit commencer par une lettre, peut contenir des lettres, chiffres et trait de soulignement.</string>
     <string name="function_already_exists">Une fonction portant le même nom existe déjà !</string>
     <string name="function_is_empty">Le corps de la fonction ne peut pas être vide !</string>
-    <string name="function_param_not_empty">Il ne peut y avoir aucun paramètre à la fonction !</string>
     <string name="function_removal_confirmation_question">Voulez-vous vraiment supprimer la fonction \'%s\' ?</string>
     <string name="empty_function_error">Impossible de créer une fonction vide !</string>
     <string name="do_not_show_messages_in_session">Ne plus afficher ce message jusqu\'à la prochaine session</string>
diff --git a/app/src/main/res/values-it/text_strings.xml b/app/src/main/res/values-it/text_strings.xml
index ebd225d4..8bded6c3 100644
--- a/app/src/main/res/values-it/text_strings.xml
+++ b/app/src/main/res/values-it/text_strings.xml
@@ -158,7 +158,6 @@ Per favore valutate Calculator++ \nsu <a href="https://market.android.com/detail
     <string name="function_name_is_not_valid">Il nome della funzione non è valido: deve iniziare con una lettera, può contenere lettere, cifre e la sottolineatura. </string>
     <string name="function_already_exists">Funzione con lo stesso nome esiste già!</string>
     <string name="function_is_empty">Il corpo della funzione non può essere vuoto!</string>
-    <string name="function_param_not_empty">I parametri della funzione non possono essere vuoti!</string>
     <string name="function_removal_confirmation_question">Vuoi veramente eliminare la funzione \'%s\'?</string>
     <string name="empty_function_error"> Impassibile creare funzioni con argomento nullo!</string>
     <string name="do_not_show_messages_in_session">Non mostrare questo messaggio fino alla prossima sessione</string>
diff --git a/app/src/main/res/values-ja/text_strings.xml b/app/src/main/res/values-ja/text_strings.xml
index 2dc04d0c..d4931bba 100644
--- a/app/src/main/res/values-ja/text_strings.xml
+++ b/app/src/main/res/values-ja/text_strings.xml
@@ -158,7 +158,6 @@
     <string name="function_name_is_not_valid">関数の名前が無効です:名前は文字で始める必要があり、文字、数字、アンダースコアを含めることができます。</string>
     <string name="function_already_exists">同じ名前を持つ関数が既に存在します!</string>
     <string name="function_is_empty">関数の中身は空にできません!</string>
-    <string name="function_param_not_empty">関数のパラメーターは空にはできません！</string>
     <string name="function_removal_confirmation_question">本当に関数\'%s\'を削除してもよろしいでしょうか?</string>
     <string name="empty_function_error">空の関数を作成することはできません！</string>
     <string name="do_not_show_messages_in_session">次のセッションまでこのメッセージを表示しません</string>
diff --git a/app/src/main/res/values-nl/text_strings.xml b/app/src/main/res/values-nl/text_strings.xml
index 3ea8991b..01f162c8 100644
--- a/app/src/main/res/values-nl/text_strings.xml
+++ b/app/src/main/res/values-nl/text_strings.xml
@@ -149,7 +149,6 @@
     <string name="function_name_is_not_valid">Ongeldige functienaam: naam moet starten met een letter en kan Letters,  cijfers en \'_\' bevatten. </string>
     <string name="function_already_exists">Functienaam is al gebruikt!</string>
     <string name="function_is_empty">Functie mag niet leeg zijn!</string>
-    <string name="function_param_not_empty">Functieparameter mag niet leeg zijn!</string>
     <string name="function_removal_confirmation_question">Wilt u de functie  \'%s\' echt verwijderen?</string>
     <string name="empty_function_error">Niet mogelijk om een lege functie te maken!</string>
     <string name="do_not_show_messages_in_session">Dit bericht niet meer weergeven tot de volgende sessie</string>
diff --git a/app/src/main/res/values-pl/text_strings.xml b/app/src/main/res/values-pl/text_strings.xml
index 9e10d026..2fec5c80 100644
--- a/app/src/main/res/values-pl/text_strings.xml
+++ b/app/src/main/res/values-pl/text_strings.xml
@@ -153,7 +153,6 @@ Proszę, oceń Calculator++ \nna<a href="https://market.android.com/details?id=o
     <string name="function_name_is_not_valid">Nazwa funkcji jest nieprawidłowa: nazwa musi zaczynać się od litery, może zawierać litery, cyfry i znak podkreślenia.</string>
     <string name="function_already_exists">Funkcja o takiej samej nazwie już istnieje!</string>
     <string name="function_is_empty">Definicja funkcji nie może być pusta!</string>
-    <string name="function_param_not_empty">Funkcja powinna posiadać parametry!</string>
     <string name="function_removal_confirmation_question">Czy na pewno chcesz usunąć funkcję \'%s\'?</string>
     <string name="empty_function_error">Nie można utworzyć pustej funkcji!</string>
     <string name="do_not_show_messages_in_session">Nie pokazuj tej wiadomości do czasu następnej sesji</string>
diff --git a/app/src/main/res/values-pt-rBR/text_strings.xml b/app/src/main/res/values-pt-rBR/text_strings.xml
index f2f96a7e..6ddb7ec4 100644
--- a/app/src/main/res/values-pt-rBR/text_strings.xml
+++ b/app/src/main/res/values-pt-rBR/text_strings.xml
@@ -149,7 +149,6 @@
     <string name="function_name_is_not_valid">O nome da função não é válido: o nome deve começar com uma letra, pode conter letras, dígitos e sublinhado.</string>
     <string name="function_already_exists">Já existe uma função com o mesmo nome!</string>
     <string name="function_is_empty">O corpo da função não pode ficar vazio!</string>
-    <string name="function_param_not_empty">O parâmetro da função não pode ficar vazio!</string>
     <string name="function_removal_confirmation_question">Você quer realmente excluir a função \'%s\'?</string>
     <string name="empty_function_error">Não é possível criar uma função vazia!</string>
     <string name="do_not_show_messages_in_session">Não mostre esta mensagem até a próxima sessão</string>
diff --git a/app/src/main/res/values-pt-rPT/text_strings.xml b/app/src/main/res/values-pt-rPT/text_strings.xml
index 9ad2c08c..41a74286 100644
--- a/app/src/main/res/values-pt-rPT/text_strings.xml
+++ b/app/src/main/res/values-pt-rPT/text_strings.xml
@@ -149,7 +149,6 @@
     <string name="function_name_is_not_valid">Nome da função não é válido: o nome deve começar com uma letra e pode conter letras, dígitos e o caracter \"_\".</string>
     <string name="function_already_exists">Já existe uma função com o mesmo nome !</string>
     <string name="function_is_empty">Corpo da função não pode ser vazio!</string>
-    <string name="function_param_not_empty">Parâmetro da função não deve ser vazio!</string>
     <string name="function_removal_confirmation_question">Pretende apagar a função \'%s\'?</string>
     <string name="empty_function_error">Não é possível criar função vazia!</string>
     <string name="do_not_show_messages_in_session">Não mostrar esta mensagem até à próxima sessão</string>
diff --git a/app/src/main/res/values-ru/text_strings.xml b/app/src/main/res/values-ru/text_strings.xml
index a5191921..c7e87a93 100644
--- a/app/src/main/res/values-ru/text_strings.xml
+++ b/app/src/main/res/values-ru/text_strings.xml
@@ -175,7 +175,6 @@
 	</string>
     <string name="function_already_exists">Функция с таким именем уже существует!</string>
     <string name="function_is_empty">Тело функции не должно быть пустым!</string>
-    <string name="function_param_not_empty">Имя параметра не должно быть пустым!</string>
     <string name="function_removal_confirmation_question">Вы действительно хотите удалить функцию \'%s\'?</string>
     <string name="empty_function_error">Невозможно создать пустую функцию!</string>
     <string name="do_not_show_messages_in_session">Не показывать это сообщение до следующего запуска программы</string>
diff --git a/app/src/main/res/values-tr/text_strings.xml b/app/src/main/res/values-tr/text_strings.xml
index bb252fb5..313fce2e 100644
--- a/app/src/main/res/values-tr/text_strings.xml
+++ b/app/src/main/res/values-tr/text_strings.xml
@@ -152,7 +152,6 @@ Google Play</a>,\n yorum yazın yada \n uygulamayı tartışın \non
     <string name="function_name_is_not_valid">Fonksiyon adı geçerli değil: isim bir harf ile başlamalıdır, harf, rakam ve alt çizli içerebilir.</string>
     <string name="function_already_exists">Aynı isimi bir fonksiyon zaten var!</string>
     <string name="function_is_empty">Fonksiyon gövdesi boş bırakılamaz!</string>
-    <string name="function_param_not_empty">Fonksiyon parametresi boş olamaz!</string>
     <string name="function_removal_confirmation_question">%s fonksiyonunu gerçekten silme istiyor musunuz?</string>
     <string name="empty_function_error">Boş fonksiyon oluşturulamaz!</string>
     <string name="do_not_show_messages_in_session">Yeni bir oturuma kadar bu mesajı gösterme</string>
diff --git a/app/src/main/res/values-uk/text_strings.xml b/app/src/main/res/values-uk/text_strings.xml
index dd7fdd81..34b6f2d4 100644
--- a/app/src/main/res/values-uk/text_strings.xml
+++ b/app/src/main/res/values-uk/text_strings.xml
@@ -165,7 +165,6 @@
     <string name="function_name_is_not_valid">Неприпустиме ім\'я функції: ім\'я має починатися з літери, може містити літери, цифри та знак підкреслення (_).</string>
     <string name="function_already_exists">Функція з таким ім\'ям вже існує!</string>
     <string name="function_is_empty">Тіло функції не може бути відсутнім!</string>
-    <string name="function_param_not_empty">Параметр функції не може бути відсутнім!</string>
     <string name="function_removal_confirmation_question">Ви дійсно хочете видалити функцію \'%s\'?</string>
     <string name="empty_function_error">Не вдалося створити порожню функцію!</string>
     <string name="do_not_show_messages_in_session">Не показувати це повідомлення до наступної сесії</string>
diff --git a/app/src/main/res/values-v11/styles.xml b/app/src/main/res/values-v11/styles.xml
new file mode 100644
index 00000000..362586c1
--- /dev/null
+++ b/app/src/main/res/values-v11/styles.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <style name="CppText.Editor.Widget" parent="CppText.Editor.BaseWidget">
+        <item name="android:textIsSelectable">true</item>
+    </style>
+</resources>
\ No newline at end of file
diff --git a/app/src/main/res/values-v14/styles.xml b/app/src/main/res/values-v14/styles.xml
new file mode 100644
index 00000000..0a7d3a72
--- /dev/null
+++ b/app/src/main/res/values-v14/styles.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <style name="CppKeyboardButton" parent="BaseCppKeyboardButton">
+        <item name="android:textAllCaps">false</item>
+    </style>
+</resources>
\ No newline at end of file
diff --git a/app/src/main/res/values-v21/theme_material.xml b/app/src/main/res/values-v21/theme_material.xml
new file mode 100644
index 00000000..df56e71d
--- /dev/null
+++ b/app/src/main/res/values-v21/theme_material.xml
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <style name="CppKeyboardButton.Material.Digit" parent="CppKeyboardButton">
+        <item name="android:background">@drawable/material_button_dark</item>
+        <item name="android:stateListAnimator">@null</item>
+    </style>
+</resources>
\ No newline at end of file
diff --git a/app/src/main/res/values-v21/theme_material_light.xml b/app/src/main/res/values-v21/theme_material_light.xml
new file mode 100644
index 00000000..a2cad0d9
--- /dev/null
+++ b/app/src/main/res/values-v21/theme_material_light.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+
+    <style name="CppKeyboardButton.Material.Light.Digit" parent="CppKeyboardButton">
+        <item name="android:background">@drawable/material_button_light</item>
+        <item name="android:stateListAnimator">@null</item>
+    </style>
+</resources>
\ No newline at end of file
diff --git a/app/src/main/res/values-vi/text_strings.xml b/app/src/main/res/values-vi/text_strings.xml
index 104858dd..cf3e1d2e 100644
--- a/app/src/main/res/values-vi/text_strings.xml
+++ b/app/src/main/res/values-vi/text_strings.xml
@@ -153,7 +153,6 @@ Google Play</a>,\n để lại ý kiến hoặc \n thảo luận về ứng dụ
     <string name="function_name_is_not_valid">Tên của hàm không hợp lệ: tên phải bắt đầu với một chữ cái, có thể chứa chữ cái, chữ số và gạch dưới.</string>
     <string name="function_already_exists">Hàm cùng tên đã tồn tại!</string>
     <string name="function_is_empty">Hàm không được rỗng!</string>
-    <string name="function_param_not_empty">Tham số hàm không được rỗng!</string>
     <string name="function_removal_confirmation_question">Bạn có thực sự muốn xóa \'%s\' hàm?</string>
     <string name="empty_function_error">Không thể tạo ra hàm rỗng!</string>
     <string name="do_not_show_messages_in_session">Không hiện thông báo này cho đến khi phiên tiếp theo</string>
diff --git a/app/src/main/res/values-zh-rCN/text_strings.xml b/app/src/main/res/values-zh-rCN/text_strings.xml
index b45f8d3e..a9adfaa8 100644
--- a/app/src/main/res/values-zh-rCN/text_strings.xml
+++ b/app/src/main/res/values-zh-rCN/text_strings.xml
@@ -152,7 +152,6 @@
     <string name="function_name_is_not_valid">函数名称无效：名称必须以字母开头，可以包含字母、数字和下划线。</string>
     <string name="function_already_exists">已经存在相同名称的函数！</string>
     <string name="function_is_empty">函数主体不能为空！</string>
-    <string name="function_param_not_empty">函数参数不能为空！</string>
     <string name="function_removal_confirmation_question">确认要删除 \'%s\' 函数吗？</string>
     <string name="empty_function_error">无法创建空函数 ！</string>
     <string name="do_not_show_messages_in_session">不再显示此消息直到下一个会话</string>
diff --git a/app/src/main/res/values-zh-rTW/text_strings.xml b/app/src/main/res/values-zh-rTW/text_strings.xml
index 81059538..46139265 100644
--- a/app/src/main/res/values-zh-rTW/text_strings.xml
+++ b/app/src/main/res/values-zh-rTW/text_strings.xml
@@ -153,7 +153,6 @@ Google Play</a>，\n留下評論或是\n討論這個應用程式\n於
     <string name="function_name_is_not_valid">函數名稱無效：名稱必須以字母開頭，可以包含字母、數字和底線。</string>
     <string name="function_already_exists">相同名稱的函數已經存在！</string>
     <string name="function_is_empty">函數主體不能空白！</string>
-    <string name="function_param_not_empty">函數參數不應該是空白！</string>
     <string name="function_removal_confirmation_question">你真的要刪除函數 \'%s\' 嗎？</string>
     <string name="empty_function_error">無法新增空白函數！</string>
     <string name="do_not_show_messages_in_session">直到下一次不要顯示這訊息</string>
diff --git a/app/src/main/res/values/arrays.xml b/app/src/main/res/values/arrays.xml
index 9445d300..64b7eecb 100644
--- a/app/src/main/res/values/arrays.xml
+++ b/app/src/main/res/values/arrays.xml
@@ -75,19 +75,6 @@
         <item>simple</item>
     </string-array>
 
-    <string-array name="cpp_haptic_feedback_names">
-        <item>@string/p_calc_haptic_feedback_strength_disabled</item>
-        <item>@string/p_calc_haptic_feedback_strength_short</item>
-        <item>@string/p_calc_haptic_feedback_strength_middle</item>
-        <item>@string/p_calc_haptic_feedback_strength_long</item>
-    </string-array>
-    <string-array name="cpp_haptic_feedback_values" translatable="false">
-        <item>0</item>
-        <item>30</item>
-        <item>60</item>
-        <item>100</item>
-    </string-array>
-
     <string-array name="p_angle_units_names">
         <item>@string/p_deg</item>
         <item>@string/p_rad</item>
@@ -114,39 +101,8 @@
         <item>bin</item>
     </string-array>
 
-    <!--
-     monochrome,
-    dashed,
-    dotted,
-    dash_dotted;
-    -->
-    <string-array name="cpp_plot_line_style_names">
-        <item>@string/cpp_solid_line_style</item>
-        <item>@string/cpp_dashed_line_style</item>
-        <item>@string/cpp_dotted_line_style</item>
-        <item>@string/cpp_dash_dotted_line_style</item>
-    </string-array>
-
-    <string-array name="cpp_plot_line_color_type_names">
-        <item>@string/cpp_monochrome_line_color_type</item>
-        <item>@string/cpp_color_map_line_color_type</item>
-    </string-array>
-
-    <string-array name="cpp_plot_line_color_names">
-        <item>@string/p_white_line_color</item>
-        <item>@string/p_blue_line_color</item>
-        <item>@string/p_red_line_color</item>
-        <item>@string/p_green_line_color</item>
-        <item>@string/p_grey_line_color</item>
-    </string-array>
-
     <string-array name="cpp_modes">
         <item>@string/cpp_wizard_mode_simple</item>
         <item>@string/cpp_wizard_mode_engineer</item>
     </string-array>
-
-    <string-array name="cpp_layouts">
-        <item>@string/cpp_wizard_layout_big_buttons</item>
-        <item>@string/cpp_wizard_layout_optimized</item>
-    </string-array>
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/colors.xml b/app/src/main/res/values/colors.xml
index 9cffc0c2..064b58e2 100644
--- a/app/src/main/res/values/colors.xml
+++ b/app/src/main/res/values/colors.xml
@@ -48,8 +48,6 @@
     <color name="cpp_metro_purple">#651456</color>
     <color name="cpp_widget_cursor">#ff707070</color>
     <color name="cpp_widget_ripple">#40ffffff</color>
-    <color name="cpp_status_bar">#ff131313</color>
-    <color name="cpp_status_bar_light">#262626</color>
 
     <color name="cpp_wizard_disabled_text">#66ffffff</color>
 
@@ -61,8 +59,6 @@
     <color name="cpp_pane_bg_light">#ffeae5e3</color>
     <color name="grey_900">#212121</color>
     <color name="grey_950">#101010</color>
-    <color name="grey_600">#757575</color>
     <color name="grey_800">#424242</color>
-    <color name="blue_grey_800">#37474F</color>
 
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/dimens.xml b/app/src/main/res/values/dimens.xml
index 7e6fede8..13285bcd 100644
--- a/app/src/main/res/values/dimens.xml
+++ b/app/src/main/res/values/dimens.xml
@@ -10,17 +10,12 @@
     <dimen name="cpp_button_padding">1px</dimen>
     <dimen name="cpp_button_corner">1dp</dimen>
 
-    <dimen name="cpp_fragment_text_size">15sp</dimen>
-    <dimen name="cpp_fragment_title_text_size">20sp</dimen>
-
     <dimen name="cpp_keyboard_button_text_size">30dp</dimen>
     <dimen name="cpp_keyboard_simple_image_button_padding">12dp</dimen>
 
     <dimen name="cpp_display_text_size">25sp</dimen>
     <dimen name="cpp_min_editor_text_size">24sp</dimen>
     <dimen name="cpp_pane_margin">2dp</dimen>
-    <dimen name="cpp_li_text_size">16sp</dimen>
-    <dimen name="cpp_li_secondary_text_size">14sp</dimen>
 
     <dimen name="cpp_onscreen_display_text_size">20sp</dimen>
     <dimen name="cpp_onscreen_header_button_text_size">10dp</dimen>
diff --git a/app/src/main/res/values/styles.xml b/app/src/main/res/values/styles.xml
index e72d20b0..9f567618 100644
--- a/app/src/main/res/values/styles.xml
+++ b/app/src/main/res/values/styles.xml
@@ -26,8 +26,8 @@
         <item name="android:textSize">@dimen/cpp_text_size</item>
     </style>
 
-    <style name="CppKeyboardButton">
-        <item name="android:textAllCaps">false</item>
+    <style name="CppKeyboardButton" parent="BaseCppKeyboardButton"/>
+    <style name="BaseCppKeyboardButton">
         <item name="android:layout_width">0dp</item>
         <item name="android:layout_height">match_parent</item>
         <item name="android:layout_weight">1</item>
@@ -117,12 +117,12 @@
         <item name="android:background">@color/cpp_main_bg_light</item>
     </style>
 
-    <style name="CppText.Editor.Widget" parent="CppText.Editor">
+    <style name="CppText.Editor.Widget" parent="CppText.Editor.BaseWidget"/>
+    <style name="CppText.Editor.BaseWidget" parent="CppText.Editor">
         <item name="android:textSize">@dimen/cpp_widget_editor_text_size</item>
         <item name="android:textColor">@color/cpp_text</item>
         <item name="android:scrollbars">vertical</item>
         <item name="android:singleLine">false</item>
-        <item name="android:textIsSelectable">true</item>
     </style>
 
     <style name="CppText.Editor.Widget.Light" parent="CppText.Editor.Widget">
@@ -335,12 +335,6 @@
         <item name="android:ellipsize">end</item>
     </style>
 
-    <style name="CppListViewItemTextSecondary">
-        <item name="android:textAppearance">@style/TextAppearance.AppCompat</item>
-        <item name="android:textColor">?android:attr/textColorSecondary</item>
-        <item name="android:textSize">@dimen/cpp_li_secondary_text_size</item>
-    </style>
-
     <style name="CppListViewItemTextPrimary.History" parent="CppListItemText.Primary">
         <item name="android:maxLines">2</item>
         <item name="android:ellipsize">end</item>
diff --git a/app/src/main/res/values/theme_material.xml b/app/src/main/res/values/theme_material.xml
index 50d8604a..28fbf239 100644
--- a/app/src/main/res/values/theme_material.xml
+++ b/app/src/main/res/values/theme_material.xml
@@ -24,7 +24,6 @@
 
     <style name="CppKeyboardButton.Material.Digit" parent="CppKeyboardButton">
         <item name="android:background">@drawable/material_button_dark</item>
-        <item name="android:stateListAnimator">@null</item>
     </style>
 
     <style name="CppKeyboardButton.Material.Control" parent="CppKeyboardButton.Material.Digit" />
diff --git a/app/src/main/res/values/theme_material_light.xml b/app/src/main/res/values/theme_material_light.xml
index 2d9f6f9f..06664524 100644
--- a/app/src/main/res/values/theme_material_light.xml
+++ b/app/src/main/res/values/theme_material_light.xml
@@ -24,7 +24,6 @@
 
     <style name="CppKeyboardButton.Material.Light.Digit" parent="CppKeyboardButton">
         <item name="android:background">@drawable/material_button_light</item>
-        <item name="android:stateListAnimator">@null</item>
     </style>
 
     <style name="CppKeyboardButton.Material.Light.Operation" parent="CppKeyboardButton.Material.Digit">