diff --git a/app/src/main/java/org/solovyev/android/calculator/CalculatorActivity.java b/app/src/main/java/org/solovyev/android/calculator/CalculatorActivity.java
index afc0ba7c..258e401c 100644
--- a/app/src/main/java/org/solovyev/android/calculator/CalculatorActivity.java
+++ b/app/src/main/java/org/solovyev/android/calculator/CalculatorActivity.java
@@ -22,15 +22,6 @@
 
 package org.solovyev.android.calculator;
 
-import static android.content.pm.ActivityInfo.SCREEN_ORIENTATION_PORTRAIT;
-import static android.content.pm.ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED;
-import static android.view.WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON;
-import static org.solovyev.android.calculator.Preferences.Gui.preventScreenFromFading;
-import static org.solovyev.android.calculator.release.ReleaseNotes.hasReleaseNotes;
-import static org.solovyev.android.wizard.WizardUi.continueWizard;
-import static org.solovyev.android.wizard.WizardUi.createLaunchIntent;
-import static org.solovyev.android.wizard.WizardUi.startWizard;
-
 import android.content.Context;
 import android.content.SharedPreferences;
 import android.content.res.Resources;
@@ -62,13 +53,22 @@ import org.solovyev.android.wizard.Wizard;
 import org.solovyev.android.wizard.Wizards;
 import org.solovyev.common.Objects;
 
-import butterknife.Bind;
-import butterknife.ButterKnife;
-
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import javax.inject.Inject;
 
+import butterknife.Bind;
+import butterknife.ButterKnife;
+
+import static android.content.pm.ActivityInfo.SCREEN_ORIENTATION_PORTRAIT;
+import static android.content.pm.ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED;
+import static android.view.WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON;
+import static org.solovyev.android.calculator.Preferences.Gui.keepScreenOn;
+import static org.solovyev.android.calculator.release.ReleaseNotes.hasReleaseNotes;
+import static org.solovyev.android.wizard.WizardUi.continueWizard;
+import static org.solovyev.android.wizard.WizardUi.createLaunchIntent;
+import static org.solovyev.android.wizard.WizardUi.startWizard;
+
 public class CalculatorActivity extends BaseActivity implements SharedPreferences.OnSharedPreferenceChangeListener, Toolbar.OnMenuItemClickListener {
 
     @Inject
@@ -236,7 +236,7 @@ public class CalculatorActivity extends BaseActivity implements SharedPreference
         }
 
         final Window window = getWindow();
-        if (preventScreenFromFading.getPreference(preferences)) {
+        if (keepScreenOn.getPreference(preferences)) {
             window.addFlags(FLAG_KEEP_SCREEN_ON);
         } else {
             window.clearFlags(FLAG_KEEP_SCREEN_ON);
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 f9706664..b6b41890 100644
--- a/app/src/main/java/org/solovyev/android/calculator/Preferences.java
+++ b/app/src/main/java/org/solovyev/android/calculator/Preferences.java
@@ -31,11 +31,11 @@ import android.graphics.Color;
 import android.provider.Settings;
 import android.support.annotation.ColorRes;
 import android.support.annotation.LayoutRes;
+import android.support.annotation.NonNull;
 import android.support.annotation.StyleRes;
 import android.util.SparseArray;
 import android.view.ContextThemeWrapper;
-import jscl.AngleUnit;
-import jscl.NumeralBase;
+
 import org.solovyev.android.Check;
 import org.solovyev.android.calculator.about.AboutActivity;
 import org.solovyev.android.calculator.functions.FunctionsActivity;
@@ -46,15 +46,23 @@ 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.*;
+import org.solovyev.android.prefs.BooleanPreference;
+import org.solovyev.android.prefs.IntegerPreference;
+import org.solovyev.android.prefs.NumberToStringPreference;
+import org.solovyev.android.prefs.Preference;
+import org.solovyev.android.prefs.StringPreference;
 
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
 import java.text.DecimalFormatSymbols;
 import java.util.EnumMap;
 import java.util.Locale;
 import java.util.Map;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+import jscl.AngleUnit;
+import jscl.NumeralBase;
+
 import static org.solovyev.android.Android.isPhoneModel;
 import static org.solovyev.android.DeviceModel.samsung_galaxy_s;
 import static org.solovyev.android.DeviceModel.samsung_galaxy_s_2;
@@ -79,9 +87,13 @@ public final class Preferences {
             final SharedPreferences.Editor editor = preferences.edit();
             if (!Gui.vibrateOnKeypress.isSet(preferences)) {
                 //noinspection deprecation
-                Gui.vibrateOnKeypress.putPreference(editor, Gui.hapticFeedback.getPreference(preferences) > 0);
+                Gui.vibrateOnKeypress.putPreference(editor, Deleted.hapticFeedback.getPreference(preferences) > 0);
             }
-            final Gui.Layout layout = Gui.layout.getPreference(preferences);
+            migratePreference(preferences, editor, Gui.highlightText, Deleted.colorDisplay);
+            migratePreference(preferences, editor, Gui.keepScreenOn, Deleted.preventScreenFromFading);
+            migratePreference(preferences, editor, Gui.theme, Deleted.oldTheme);
+            migratePreference(preferences, editor, Gui.layout, Deleted.oldLayout);
+            final Gui.Layout layout = Deleted.oldLayout.getPreference(preferences);
             if (layout == Gui.Layout.main_cellphone) {
                 Gui.layout.putDefault(editor);
             } else if (layout == Gui.Layout.main_calculator_mobile) {
@@ -93,6 +105,12 @@ public final class Preferences {
         }
     }
 
+    private static <T> void migratePreference(@Nonnull SharedPreferences preferences, @NonNull SharedPreferences.Editor editor, @NonNull Preference<T> to, @NonNull Preference<T> from) {
+        if (!to.isSet(preferences)) {
+            to.putPreference(editor, from.getPreferenceNoError(preferences));
+        }
+    }
+
     private static void setInitialDefaultValues(@Nonnull Application application, @Nonnull SharedPreferences preferences, @Nonnull SharedPreferences.Editor editor) {
         if (!Engine.Preferences.groupingSeparator.isSet(preferences)) {
             final Locale locale = Locale.getDefault();
@@ -128,7 +146,7 @@ public final class Preferences {
         Gui.showEqualsButton.tryPutDefault(preferences, editor);
         Gui.autoOrientation.tryPutDefault(preferences, editor);
         Gui.hideNumeralBaseDigits.tryPutDefault(preferences, editor);
-        Gui.preventScreenFromFading.tryPutDefault(preferences, editor);
+        Gui.keepScreenOn.tryPutDefault(preferences, editor);
         Gui.language.tryPutDefault(preferences, editor);
 
         Graph.plotImag.tryPutDefault(preferences, editor);
@@ -267,10 +285,8 @@ public final class Preferences {
 
     public static class Gui {
 
-        public static final Preference<Theme> theme = StringPreference.ofEnum("org.solovyev.android.calculator.CalculatorActivity_calc_theme", Theme.material_theme, Theme.class);
-        public static final Preference<Layout> layout = StringPreference.ofEnum(
-                "org.solovyev.android.calculator.CalculatorActivity_calc_layout", Layout.simple,
-                Layout.class);
+        public static final Preference<Theme> theme = StringPreference.ofEnum("gui.theme", Theme.material_theme, Theme.class);
+        public static final Preference<Layout> layout = StringPreference.ofEnum("gui.layout", Layout.simple, Layout.class);
         public static final Preference<String> language = StringPreference.of("gui.language", Languages.SYSTEM_LANGUAGE_CODE);
         public static final Preference<Boolean> feedbackWindowShown = BooleanPreference.of("feedback_window_shown", false);
         public static final Preference<Boolean> showReleaseNotes = BooleanPreference.of("org.solovyev.android.calculator.CalculatorActivity_show_release_notes", true);
@@ -278,11 +294,9 @@ public final class Preferences {
         public static final Preference<Boolean> showEqualsButton = BooleanPreference.of("showEqualsButton", true);
         public static final Preference<Boolean> autoOrientation = BooleanPreference.of("autoOrientation", true);
         public static final Preference<Boolean> hideNumeralBaseDigits = BooleanPreference.of("hideNumeralBaseDigits", true);
-        public static final Preference<Boolean> preventScreenFromFading = BooleanPreference.of("preventScreenFromFading", true);
-        public static final Preference<Boolean> colorDisplay = BooleanPreference.of("org.solovyev.android.calculator.CalculatorModel_color_display", true);
+        public static final Preference<Boolean> keepScreenOn = BooleanPreference.of("gui.keepScreenOn", true);
+        public static final Preference<Boolean> highlightText = BooleanPreference.of("gui.highlightText", true);
         public static final Preference<Boolean> vibrateOnKeypress = BooleanPreference.of("gui.vibrateOnKeypress", true);
-        @Deprecated
-        public static final Preference<Long> hapticFeedback = NumberToStringPreference.of("hapticFeedback", 60L, Long.class);
 
         @Nonnull
         public static Theme getTheme(@Nonnull SharedPreferences preferences) {
@@ -400,4 +414,12 @@ public final class Preferences {
     public static class Graph {
         public static final Preference<Boolean> plotImag = BooleanPreference.of("graph_plot_imag", false);
     }
+
+    private static class Deleted {
+        static final Preference<Long> hapticFeedback = NumberToStringPreference.of("hapticFeedback", 60L, Long.class);
+        static final Preference<Boolean> colorDisplay = BooleanPreference.of("org.solovyev.android.calculator.CalculatorModel_color_display", true);
+        static final Preference<Boolean> preventScreenFromFading = BooleanPreference.of("preventScreenFromFading", true);
+        static final Preference<Gui.Theme> oldTheme = StringPreference.ofEnum("org.solovyev.android.calculator.CalculatorActivity_calc_theme", Gui.Theme.material_theme, Gui.Theme.class);
+        static final Preference<Gui.Layout> oldLayout = StringPreference.ofEnum("org.solovyev.android.calculator.CalculatorActivity_calc_layout", Gui.Layout.simple, Gui.Layout.class);
+    }
 }
diff --git a/app/src/main/java/org/solovyev/android/calculator/floating/FloatingCalculatorService.java b/app/src/main/java/org/solovyev/android/calculator/floating/FloatingCalculatorService.java
index 3389decd..0f3d7280 100644
--- a/app/src/main/java/org/solovyev/android/calculator/floating/FloatingCalculatorService.java
+++ b/app/src/main/java/org/solovyev/android/calculator/floating/FloatingCalculatorService.java
@@ -22,8 +22,6 @@
 
 package org.solovyev.android.calculator.floating;
 
-import static org.solovyev.android.calculator.App.cast;
-
 import android.app.NotificationManager;
 import android.app.PendingIntent;
 import android.app.Service;
@@ -50,6 +48,8 @@ import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import javax.inject.Inject;
 
+import static org.solovyev.android.calculator.App.cast;
+
 public class FloatingCalculatorService extends Service implements FloatingViewListener, SharedPreferences.OnSharedPreferenceChangeListener {
 
     private static final String SHOW_WINDOW_ACTION = "org.solovyev.android.calculator.onscreen.SHOW_WINDOW";
diff --git a/app/src/main/java/org/solovyev/android/calculator/view/EditorTextProcessor.java b/app/src/main/java/org/solovyev/android/calculator/view/EditorTextProcessor.java
index 82ccee12..c2c47911 100644
--- a/app/src/main/java/org/solovyev/android/calculator/view/EditorTextProcessor.java
+++ b/app/src/main/java/org/solovyev/android/calculator/view/EditorTextProcessor.java
@@ -12,7 +12,6 @@ import org.solovyev.android.calculator.text.TextProcessorEditorResult;
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
-import static org.solovyev.android.calculator.Preferences.Gui.colorDisplay;
 import static org.solovyev.android.calculator.Preferences.Gui.theme;
 
 public final class EditorTextProcessor implements TextProcessor<TextProcessorEditorResult, String>, SharedPreferences.OnSharedPreferenceChangeListener {
@@ -30,7 +29,7 @@ public final class EditorTextProcessor implements TextProcessor<TextProcessorEdi
         this.preferences = preferences;
         this.engine = engine;
         preferences.registerOnSharedPreferenceChangeListener(this);
-        onSharedPreferenceChanged(preferences, colorDisplay.getKey());
+        onSharedPreferenceChanged(preferences, Preferences.Gui.highlightText.getKey());
     }
 
     @Nonnull
@@ -57,8 +56,8 @@ public final class EditorTextProcessor implements TextProcessor<TextProcessorEdi
 
     @Override
     public void onSharedPreferenceChanged(SharedPreferences preferences, String key) {
-        if (colorDisplay.isSameKey(key)) {
-            setHighlightText(colorDisplay.getPreference(preferences));
+        if (Preferences.Gui.highlightText.isSameKey(key)) {
+            setHighlightText(Preferences.Gui.highlightText.getPreference(preferences));
         } else if (theme.isSameKey(key)) {
             final int color = getTextColor(preferences);
             textHighlighter = new TextHighlighter(color, true, engine);
diff --git a/app/src/main/res/values/preferences.xml b/app/src/main/res/values/preferences.xml
index 867d4dcf..0cd8421d 100644
--- a/app/src/main/res/values/preferences.xml
+++ b/app/src/main/res/values/preferences.xml
@@ -21,12 +21,6 @@
   -->
 
 <resources>
-    <string name="p_calc_color_display_key" translatable="false">org.solovyev.android.calculator.CalculatorModel_color_display</string>
-    <string name="p_calc_color_display" translatable="false">true</string>
-
-    <string name="p_calc_haptic_feedback_key" translatable="false">org.solovyev.android.calculator.CalculatorModel_haptic_feedback</string>
-    <string name="p_calc_haptic_feedback" translatable="false">false</string>
-
 	<string name="p_calc_use_back_button_as_prev_key" translatable="false">
 		org.solovyev.android.calculator.CalculatorActivity_use_back_button_as_prev
 	</string>
@@ -38,12 +32,6 @@
 
     <string name="p_calc_history" translatable="false">org.solovyev.android.calculator.CalculatorModel_history</string>
 
-    <string name="p_calc_theme_key" translatable="false">org.solovyev.android.calculator.CalculatorActivity_calc_theme</string>
-    <string name="p_calc_theme" translatable="false">default_theme</string>
-
-    <string name="p_calc_layout_key" translatable="false">org.solovyev.android.calculator.CalculatorActivity_calc_layout</string>
-    <string name="p_calc_layout" translatable="false">main_calculator</string>
-
     <string name="p_calc_ad_free" translatable="false">false</string>
 
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/xml/preferences_appearance.xml b/app/src/main/res/xml/preferences_appearance.xml
index f102bcaa..2834ff59 100644
--- a/app/src/main/res/xml/preferences_appearance.xml
+++ b/app/src/main/res/xml/preferences_appearance.xml
@@ -31,8 +31,7 @@
         m:materialColor="@color/material_text_selector" />
 
     <android.preference.CheckBoxPreference
-        a:defaultValue="true"
-        a:key="@string/p_calc_color_display_key"
+        a:key="gui.highlightText"
         a:summary="@string/c_calc_color_display_summary"
         a:title="@string/c_calc_color_display_title" />
 
@@ -50,13 +49,13 @@
     <ListPreference
         a:entries="@array/p_theme_names"
         a:entryValues="@array/p_theme_values"
-        a:key="@string/p_calc_theme_key"
+        a:key="gui.theme"
         a:title="@string/cpp_theme" />
 
     <ListPreference
         a:entries="@array/p_layout_names"
         a:entryValues="@array/p_layout_values"
-        a:key="@string/p_calc_layout_key"
+        a:key="gui.layout"
         a:summary="@string/c_calc_layout_summary"
         a:title="@string/c_calc_layout" />
 
@@ -73,7 +72,7 @@
         a:title="@string/c_show_equals_button_title" />
 
     <android.preference.CheckBoxPreference
-        a:key="preventScreenFromFading"
+        a:key="gui.keepScreenOn"
         a:title="@string/cpp_prefs_keep_screen_on" />
 
 </PreferenceScreen>
\ No newline at end of file