diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 3b3cf64b..d1820689 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -91,7 +91,7 @@
             android:label="@string/c_operators" />
 
         <activity
-            android:name=".math.edit.CalculatorVarsActivity"
+            android:name=".variables.VariablesActivity"
             android:label="@string/c_vars_and_constants" />
         <activity
             android:name=".wizard.WizardActivity"
diff --git a/app/src/main/java/org/solovyev/android/calculator/AppComponent.java b/app/src/main/java/org/solovyev/android/calculator/AppComponent.java
index 752f4cbc..d994dfde 100644
--- a/app/src/main/java/org/solovyev/android/calculator/AppComponent.java
+++ b/app/src/main/java/org/solovyev/android/calculator/AppComponent.java
@@ -4,7 +4,7 @@ import org.solovyev.android.calculator.functions.EditFunctionFragment;
 import org.solovyev.android.calculator.history.BaseHistoryFragment;
 import org.solovyev.android.calculator.history.EditHistoryFragment;
 import org.solovyev.android.calculator.math.edit.FunctionsFragment;
-import org.solovyev.android.calculator.math.edit.VariablesFragment;
+import org.solovyev.android.calculator.variables.VariablesFragment;
 import org.solovyev.android.calculator.onscreen.CalculatorOnscreenService;
 
 import javax.inject.Singleton;
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 b45d1022..0a5322b3 100644
--- a/app/src/main/java/org/solovyev/android/calculator/CalculatorActivityLauncher.java
+++ b/app/src/main/java/org/solovyev/android/calculator/CalculatorActivityLauncher.java
@@ -41,9 +41,9 @@ import org.solovyev.android.calculator.functions.EditFunctionFragment;
 import org.solovyev.android.calculator.history.CalculatorHistoryActivity;
 import org.solovyev.android.calculator.functions.FunctionsActivity;
 import org.solovyev.android.calculator.math.edit.OperatorsActivity;
-import org.solovyev.android.calculator.math.edit.CalculatorVarsActivity;
+import org.solovyev.android.calculator.variables.VariablesActivity;
 import org.solovyev.android.calculator.math.edit.VarEditDialogFragment;
-import org.solovyev.android.calculator.math.edit.VariablesFragment;
+import org.solovyev.android.calculator.variables.VariablesFragment;
 import org.solovyev.android.calculator.matrix.CalculatorMatrixActivity;
 import org.solovyev.android.calculator.plot.CalculatorPlotActivity;
 import org.solovyev.android.calculator.plot.CalculatorPlotter;
@@ -126,7 +126,7 @@ public final class CalculatorActivityLauncher implements CalculatorEventListener
     }
 
     public static void showVars(@Nonnull final Context context, boolean detached) {
-        final Intent intent = new Intent(context, CalculatorVarsActivity.class);
+        final Intent intent = new Intent(context, VariablesActivity.class);
         Activities.addIntentFlags(intent, detached, context);
         context.startActivity(intent);
     }
@@ -148,7 +148,7 @@ public final class CalculatorActivityLauncher implements CalculatorEventListener
                     if (context instanceof AppCompatActivity) {
                         VarEditDialogFragment.showDialog(VarEditDialogFragment.Input.newFromValue(varValue), ((AppCompatActivity) context).getSupportFragmentManager());
                     } else {
-                        final Intent intent = new Intent(context, CalculatorVarsActivity.class);
+                        final Intent intent = new Intent(context, VariablesActivity.class);
                         intent.putExtra(VariablesFragment.CREATE_VAR_EXTRA_STRING, varValue);
                         Activities.addIntentFlags(intent, false, context);
                         context.startActivity(intent);
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 e0b358df..e4a984f1 100644
--- a/app/src/main/java/org/solovyev/android/calculator/CalculatorFragmentType.java
+++ b/app/src/main/java/org/solovyev/android/calculator/CalculatorFragmentType.java
@@ -30,7 +30,7 @@ import org.solovyev.android.calculator.history.RecentHistoryFragment;
 import org.solovyev.android.calculator.history.SavedHistoryFragment;
 import org.solovyev.android.calculator.math.edit.FunctionsFragment;
 import org.solovyev.android.calculator.math.edit.OperatorsFragment;
-import org.solovyev.android.calculator.math.edit.VariablesFragment;
+import org.solovyev.android.calculator.variables.VariablesFragment;
 import org.solovyev.android.calculator.matrix.CalculatorMatrixEditFragment;
 import org.solovyev.android.calculator.plot.CalculatorPlotFragment;
 import org.solovyev.android.calculator.plot.CalculatorPlotFunctionSettingsActivity;
diff --git a/app/src/main/java/org/solovyev/android/calculator/math/edit/BaseEntitiesFragment.java b/app/src/main/java/org/solovyev/android/calculator/math/edit/BaseEntitiesFragment.java
index 2894a272..8e0f6be7 100644
--- a/app/src/main/java/org/solovyev/android/calculator/math/edit/BaseEntitiesFragment.java
+++ b/app/src/main/java/org/solovyev/android/calculator/math/edit/BaseEntitiesFragment.java
@@ -31,35 +31,27 @@ import android.support.v7.widget.LinearLayoutManager;
 import android.support.v7.widget.RecyclerView;
 import android.text.ClipboardManager;
 import android.text.TextUtils;
-import android.view.ContextMenu;
-import android.view.LayoutInflater;
-import android.view.MenuItem;
-import android.view.View;
-import android.view.ViewGroup;
+import android.view.*;
 import android.widget.TextView;
-
+import butterknife.Bind;
+import butterknife.ButterKnife;
 import com.melnykov.fab.FloatingActionButton;
-
 import org.solovyev.android.Check;
 import org.solovyev.android.calculator.BaseFragment;
 import org.solovyev.android.calculator.CalculatorFragmentType;
-import org.solovyev.android.calculator.entities.Category;
 import org.solovyev.android.calculator.R;
+import org.solovyev.android.calculator.entities.Category;
 import org.solovyev.android.views.llm.DividerItemDecoration;
 import org.solovyev.common.math.MathEntity;
 import org.solovyev.common.text.Strings;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.Iterator;
 import java.util.List;
 
-import javax.annotation.Nonnull;
-import javax.annotation.Nullable;
-
-import butterknife.Bind;
-import butterknife.ButterKnife;
-
 
 public abstract class BaseEntitiesFragment<E extends MathEntity> extends BaseFragment {
 
@@ -74,9 +66,9 @@ public abstract class BaseEntitiesFragment<E extends MathEntity> extends BaseFra
     @Nonnull
     private final Handler uiHandler = new Handler();
     @Bind(R.id.entities_fab)
-    FloatingActionButton fab;
+    public FloatingActionButton fab;
     @Bind(R.id.entities_recyclerview)
-    RecyclerView recyclerView;
+    public RecyclerView recyclerView;
     private EntitiesAdapter adapter;
     @Nullable
     private String category;
@@ -92,7 +84,7 @@ public abstract class BaseEntitiesFragment<E extends MathEntity> extends BaseFra
         return result;
     }
 
-    static void putCategory(@Nonnull Bundle bundle, @Nonnull String categoryId) {
+    public static void putCategory(@Nonnull Bundle bundle, @Nonnull String categoryId) {
         bundle.putString(ARG_CATEGORY, categoryId);
     }
 
@@ -152,7 +144,7 @@ public abstract class BaseEntitiesFragment<E extends MathEntity> extends BaseFra
     protected abstract List<E> getEntities();
 
     @Nullable
-    abstract Category getCategory(@Nonnull E e);
+    protected abstract Category getCategory(@Nonnull E e);
 
     protected EntitiesAdapter getAdapter() {
         return adapter;
diff --git a/app/src/main/java/org/solovyev/android/calculator/math/edit/VarEditorSaver.java b/app/src/main/java/org/solovyev/android/calculator/math/edit/VarEditorSaver.java
index 10b79aa8..20b8b748 100644
--- a/app/src/main/java/org/solovyev/android/calculator/math/edit/VarEditorSaver.java
+++ b/app/src/main/java/org/solovyev/android/calculator/math/edit/VarEditorSaver.java
@@ -24,13 +24,16 @@ package org.solovyev.android.calculator.math.edit;
 
 import android.view.View;
 import android.widget.EditText;
-
+import jscl.text.Identifier;
+import jscl.text.ParseException;
+import jscl.text.Parser;
 import org.solovyev.android.calculator.EntitiesRegistry;
 import org.solovyev.android.calculator.Locator;
 import org.solovyev.android.calculator.R;
 import org.solovyev.android.calculator.VariablesRegistry;
 import org.solovyev.android.calculator.math.MathType;
 import org.solovyev.android.calculator.model.MathEntityBuilder;
+import org.solovyev.android.calculator.variables.VariablesFragment;
 import org.solovyev.common.math.MathEntity;
 import org.solovyev.common.msg.MessageType;
 import org.solovyev.common.text.Strings;
@@ -38,10 +41,6 @@ import org.solovyev.common.text.Strings;
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
-import jscl.text.Identifier;
-import jscl.text.ParseException;
-import jscl.text.Parser;
-
 public class VarEditorSaver<T extends MathEntity> implements View.OnClickListener {
 
     @Nonnull
diff --git a/app/src/main/java/org/solovyev/android/calculator/math/edit/CalculatorVarsActivity.java b/app/src/main/java/org/solovyev/android/calculator/variables/VariablesActivity.java
similarity index 88%
rename from app/src/main/java/org/solovyev/android/calculator/math/edit/CalculatorVarsActivity.java
rename to app/src/main/java/org/solovyev/android/calculator/variables/VariablesActivity.java
index 279c4a26..efdfca94 100644
--- a/app/src/main/java/org/solovyev/android/calculator/math/edit/CalculatorVarsActivity.java
+++ b/app/src/main/java/org/solovyev/android/calculator/variables/VariablesActivity.java
@@ -20,7 +20,7 @@
  * Site:  http://se.solovyev.org
  */
 
-package org.solovyev.android.calculator.math.edit;
+package org.solovyev.android.calculator.variables;
 
 import android.content.Intent;
 import android.os.Bundle;
@@ -31,15 +31,15 @@ import org.solovyev.android.calculator.CalculatorEventListener;
 import org.solovyev.android.calculator.CalculatorEventType;
 import org.solovyev.android.calculator.CalculatorFragmentType;
 import org.solovyev.android.calculator.R;
-import org.solovyev.android.calculator.variables.VariablesCategory;
+import org.solovyev.android.calculator.math.edit.BaseEntitiesFragment;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
-public class CalculatorVarsActivity extends BaseActivity implements CalculatorEventListener {
+public class VariablesActivity extends BaseActivity implements CalculatorEventListener {
 
-    public CalculatorVarsActivity() {
-        super(R.layout.main_empty, CalculatorVarsActivity.class.getSimpleName());
+    public VariablesActivity() {
+        super(R.layout.main_empty, VariablesActivity.class.getSimpleName());
     }
 
     @Override
diff --git a/app/src/main/java/org/solovyev/android/calculator/math/edit/VariablesFragment.java b/app/src/main/java/org/solovyev/android/calculator/variables/VariablesFragment.java
similarity index 96%
rename from app/src/main/java/org/solovyev/android/calculator/math/edit/VariablesFragment.java
rename to app/src/main/java/org/solovyev/android/calculator/variables/VariablesFragment.java
index 77736301..63c00455 100644
--- a/app/src/main/java/org/solovyev/android/calculator/math/edit/VariablesFragment.java
+++ b/app/src/main/java/org/solovyev/android/calculator/variables/VariablesFragment.java
@@ -20,7 +20,7 @@
  * Site:  http://se.solovyev.org
  */
 
-package org.solovyev.android.calculator.math.edit;
+package org.solovyev.android.calculator.variables;
 
 import android.os.Bundle;
 import android.support.annotation.NonNull;
@@ -33,6 +33,9 @@ import jscl.math.function.IConstant;
 import org.solovyev.android.calculator.*;
 import org.solovyev.android.calculator.entities.Category;
 import org.solovyev.android.calculator.math.MathType;
+import org.solovyev.android.calculator.math.edit.BaseEntitiesFragment;
+import org.solovyev.android.calculator.math.edit.MathEntityRemover;
+import org.solovyev.android.calculator.math.edit.VarEditDialogFragment;
 import org.solovyev.common.JPredicate;
 import org.solovyev.common.collections.Collections;
 import org.solovyev.common.text.Strings;