diff --git a/android-app-core/src/main/java/org/solovyev/android/calculator/CalculatorPreferences.java b/android-app-core/src/main/java/org/solovyev/android/calculator/CalculatorPreferences.java
index d4bd534c..5dada2a5 100644
--- a/android-app-core/src/main/java/org/solovyev/android/calculator/CalculatorPreferences.java
+++ b/android-app-core/src/main/java/org/solovyev/android/calculator/CalculatorPreferences.java
@@ -131,7 +131,6 @@ public final class CalculatorPreferences {
     }
 
     public static class Graph {
-        public static final Preference<Boolean> interpolate = new BooleanPreference("graph_interpolate", true);
         public static final Preference<Boolean> plotImag = new BooleanPreference("graph_plot_imag", false);
     }
 
@@ -186,7 +185,6 @@ public final class CalculatorPreferences {
         applyDefaultPreference(preferences, Gui.autoOrientation);
         applyDefaultPreference(preferences, Gui.hideNumeralBaseDigits);
 
-        applyDefaultPreference(preferences, Graph.interpolate);
         applyDefaultPreference(preferences, Graph.plotImag);
         applyDefaultPreference(preferences, History.showIntermediateCalculations);
         applyDefaultPreference(preferences, Calculations.calculateOnFly);
diff --git a/android-app/res/xml/preferences_plot.xml b/android-app/res/xml/preferences_plot.xml
index 0e4a36f1..e672f3cb 100644
--- a/android-app/res/xml/preferences_plot.xml
+++ b/android-app/res/xml/preferences_plot.xml
@@ -6,11 +6,6 @@
 
         <org.solovyev.android.ads.AdViewPreference a:layout="@layout/admob_pref"/>
 
-        <!--<android.preference.CheckBoxPreference
-                a:key="graph_interpolate"
-                a:title="@string/prefs_graph_interpolate_function"
-                a:summary="@string/prefs_graph_interpolate_function_summary"/>-->
-
         <android.preference.CheckBoxPreference
             a:key="graph_plot_imag"
             a:title="@string/cpp_prefs_graph_plot_imag_title"