diff --git a/res/values/config.xml b/res/values/config.xml
index fae38fc..1ebc4c7 100755
--- a/res/values/config.xml
+++ b/res/values/config.xml
@@ -38,6 +38,9 @@
     <!-- When true enable color temperature setting. -->
     <bool name="config_enableColorTemperature">false</bool>
 
+    <!-- Whether to show TelphonyMonitor switch in Developer Options -->
+    <bool name="config_show_telephony_monitor">false</bool>
+
     <!-- Fully-qualified class name for the implementation of the FeatureFactory to be instantiated. -->
     <string name="config_featureFactory" translatable="false">com.android.settings.overlay.FeatureFactoryImpl</string>
 
diff --git a/res/values/strings.xml b/res/values/strings.xml
index 7428d20..71fd094 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -7558,6 +7558,9 @@
     <!-- Toast message letting the user know the color temperature setting is not immediate -->
     <string name="color_temperature_toast">To apply color change, turn off screen</string>
 
+    <!-- Toast message letting the user know the how to trigger telephony monitor -->
+    <string name="telephony_monitor_toast">To apply telephony monitor change, reboot device</string>
+
     <!-- Name of the setting to disable the automatic update -->
     <string name="ota_disable_automatic_update">Automatic system updates</string>
 
diff --git a/res/xml/development_prefs.xml b/res/xml/development_prefs.xml
index 57395b4..955802d 100644
--- a/res/xml/development_prefs.xml
+++ b/res/xml/development_prefs.xml
@@ -166,6 +166,11 @@
             android:entries="@array/select_logpersist_titles"
             android:entryValues="@array/select_logpersist_values" />
 
+        <SwitchPreference
+            android:key="telephony_monitor_switch"
+            android:title="@string/telephony_monitor_switch"
+            android:summary="@string/telephony_monitor_switch_summary"/>
+
     </PreferenceCategory>
 
     <PreferenceCategory android:key="debug_networking_category"
diff --git a/src/com/android/settings/DevelopmentSettings.java b/src/com/android/settings/DevelopmentSettings.java
index 90a7a05..0451ca4 100644
--- a/src/com/android/settings/DevelopmentSettings.java
+++ b/src/com/android/settings/DevelopmentSettings.java
@@ -89,6 +89,7 @@
 import com.android.settings.dashboard.DashboardFeatureProvider;
 import com.android.settings.development.BugReportPreferenceController;
 import com.android.settings.development.BugReportInPowerPreferenceController;
+import com.android.settings.development.TelephonyMonitorPreferenceController;
 import com.android.settings.fuelgauge.InactiveApps;
 import com.android.settings.overlay.FeatureFactory;
 import com.android.settings.search.BaseSearchIndexProvider;
@@ -353,6 +354,7 @@
     private DashboardFeatureProvider mDashboardFeatureProvider;
     private BugReportPreferenceController mBugReportController;
     private BugReportInPowerPreferenceController mBugReportInPowerController;
+    private TelephonyMonitorPreferenceController mTelephonyMonitorController;
 
     public DevelopmentSettings() {
         super(UserManager.DISALLOW_DEBUGGING_FEATURES);
@@ -389,6 +391,7 @@
 
         mBugReportController = new BugReportPreferenceController(getActivity());
         mBugReportInPowerController = new BugReportInPowerPreferenceController(getActivity());
+        mTelephonyMonitorController = new TelephonyMonitorPreferenceController(getActivity());
         mWebViewAppPrefController = new WebViewAppPreferenceController(getActivity());
 
         setIfOnlyAvailableForAdmins(true);
@@ -420,6 +423,7 @@
 
         mBugReportController.displayPreference(getPreferenceScreen());
         mBugReportInPowerController.displayPreference(getPreferenceScreen());
+        mTelephonyMonitorController.displayPreference(getPreferenceScreen());
         mWebViewAppPrefController.displayPreference(getPreferenceScreen());
 
         mKeepScreenOn = (RestrictedSwitchPreference) findAndInitSwitchPref(KEEP_SCREEN_ON);
@@ -638,6 +642,7 @@
             pref.setEnabled(enabled && !mDisabledPrefs.contains(pref));
         }
         mBugReportInPowerController.enablePreference(enabled);
+        mTelephonyMonitorController.enablePreference(enabled);
         mWebViewAppPrefController.enablePreference(enabled);
         updateAllOptions();
     }
@@ -760,6 +765,7 @@
                             == PackageManager.COMPONENT_ENABLED_STATE_ENABLED);
         }
         mHaveDebugSettings |= mBugReportInPowerController.updatePreference();
+        mHaveDebugSettings |= mTelephonyMonitorController.updatePreference();
         updateSwitchPreference(mKeepScreenOn, Settings.Global.getInt(cr,
                 Settings.Global.STAY_ON_WHILE_PLUGGED_IN, 0) != 0);
         updateSwitchPreference(mBtHciSnoopLog, Settings.Secure.getInt(cr,
@@ -2382,6 +2388,11 @@
         if (mBugReportInPowerController.handlePreferenceTreeClick(preference)) {
             return true;
         }
+
+        if (mTelephonyMonitorController.handlePreferenceTreeClick(preference)) {
+            return true;
+        }
+
         if (mWebViewAppPrefController.handlePreferenceTreeClick(preference)) {
             return true;
         }
diff --git a/src/com/android/settings/development/TelephonyMonitorPreferenceController.java b/src/com/android/settings/development/TelephonyMonitorPreferenceController.java
new file mode 100644
index 0000000..135af7d
--- /dev/null
+++ b/src/com/android/settings/development/TelephonyMonitorPreferenceController.java
@@ -0,0 +1,95 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * 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.
+ */
+
+package com.android.settings.development;
+
+import android.content.Context;
+import android.os.SystemProperties;
+import android.support.v14.preference.SwitchPreference;
+import android.support.v7.preference.Preference;
+import android.support.v7.preference.PreferenceScreen;
+import android.widget.Toast;
+
+import com.android.settings.core.PreferenceController;
+import com.android.settings.R;
+
+public class TelephonyMonitorPreferenceController extends PreferenceController {
+
+    private static final String KEY_TELEPHONY_MONITOR_SWITCH = "telephony_monitor_switch";
+    static final String BUILD_TYPE = "ro.build.type";
+    static final String PROPERTY_TELEPHONY_MONITOR = "persist.radio.enable_tel_mon";
+
+    private SwitchPreference mPreference;
+
+    public TelephonyMonitorPreferenceController(Context context) {
+        super(context);
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+        if (isAvailable()) {
+            mPreference = (SwitchPreference) screen.findPreference(KEY_TELEPHONY_MONITOR_SWITCH);
+            mPreference.setChecked(SystemProperties.getBoolean(PROPERTY_TELEPHONY_MONITOR, false));
+        }
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return KEY_TELEPHONY_MONITOR_SWITCH;
+    }
+
+    @Override
+    public boolean isAvailable() {
+        return mContext.getResources().getBoolean(R.bool.config_show_telephony_monitor) &&
+                (SystemProperties.get(BUILD_TYPE).equals("userdebug") ||
+                        SystemProperties.get(BUILD_TYPE).equals("eng"));
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        updatePreference();
+    }
+
+    @Override
+    public boolean handlePreferenceTreeClick(Preference preference) {
+        if (KEY_TELEPHONY_MONITOR_SWITCH.equals(preference.getKey())) {
+            final SwitchPreference switchPreference = (SwitchPreference) preference;
+            SystemProperties.set(PROPERTY_TELEPHONY_MONITOR,
+                    switchPreference.isChecked() ? "true" : "false");
+            Toast.makeText(mContext, R.string.telephony_monitor_toast,
+                    Toast.LENGTH_LONG).show();
+            return true;
+        }
+        return false;
+    }
+
+    public void enablePreference(boolean enabled) {
+        if (isAvailable()) {
+            mPreference.setEnabled(enabled);
+        }
+    }
+
+    public boolean updatePreference() {
+        if (!isAvailable()) {
+            return false;
+        }
+        final boolean enabled = SystemProperties.getBoolean(PROPERTY_TELEPHONY_MONITOR, false);
+        mPreference.setChecked(enabled);
+        return enabled;
+    }
+
+}
diff --git a/tests/robotests/src/com/android/settings/development/TelephonyMonitorPreferenceControllerTest.java b/tests/robotests/src/com/android/settings/development/TelephonyMonitorPreferenceControllerTest.java
new file mode 100644
index 0000000..5167c68
--- /dev/null
+++ b/tests/robotests/src/com/android/settings/development/TelephonyMonitorPreferenceControllerTest.java
@@ -0,0 +1,189 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * 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.
+ */
+
+package com.android.settings.development;
+
+import android.content.Context;
+import android.os.SystemProperties;
+import android.support.v14.preference.SwitchPreference;
+import android.support.v7.preference.PreferenceScreen;
+
+import com.android.settings.R;
+import com.android.settings.SettingsRobolectricTestRunner;
+import com.android.settings.TestConfig;
+import com.android.settings.testutils.shadow.SettingsShadowSystemProperties;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Answers;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.annotation.Config;
+import org.robolectric.shadows.ShadowApplication;
+import org.robolectric.shadows.ShadowToast;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@RunWith(SettingsRobolectricTestRunner.class)
+@Config(manifest = TestConfig.MANIFEST_PATH, sdk = TestConfig.SDK_VERSION)
+public class TelephonyMonitorPreferenceControllerTest {
+
+    @Mock(answer = Answers.RETURNS_DEEP_STUBS)
+    private Context mContext;
+    @Mock
+    private PreferenceScreen mScreen;
+    @Mock
+    private SwitchPreference mPreference;
+
+    private TelephonyMonitorPreferenceController mController;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        SettingsShadowSystemProperties.clear();
+        mController = new TelephonyMonitorPreferenceController(mContext);
+        when(mScreen.findPreference(mController.getPreferenceKey())).thenReturn(mPreference);
+        when(mPreference.getKey()).thenReturn(mController.getPreferenceKey());
+    }
+
+    @Config(shadows = {SettingsShadowSystemProperties.class})
+    @Test
+    public void isAvailable_trueShowFlagWithUserdebugBuild_shouldReturnTrue() {
+        when(mContext.getResources().getBoolean(R.bool.config_show_telephony_monitor))
+                .thenReturn(true);
+        SettingsShadowSystemProperties.set(
+                TelephonyMonitorPreferenceController.BUILD_TYPE, "userdebug");
+
+        assertThat(mController.isAvailable()).isTrue();
+    }
+
+    @Config(shadows = {SettingsShadowSystemProperties.class})
+    @Test
+    public void isAvailable_trueShowFlagWithEngBuild_shouldReturnTrue() {
+        when(mContext.getResources().getBoolean(R.bool.config_show_telephony_monitor))
+                .thenReturn(true);
+        SettingsShadowSystemProperties.set(
+                TelephonyMonitorPreferenceController.BUILD_TYPE, "eng");
+
+        assertThat(mController.isAvailable()).isTrue();
+    }
+
+    @Config(shadows = {SettingsShadowSystemProperties.class})
+    @Test
+    public void isAvailable_trueShowFlagWithUserBuild_shouldReturnFalse() {
+        when(mContext.getResources().getBoolean(R.bool.config_show_telephony_monitor))
+                .thenReturn(true);
+        SettingsShadowSystemProperties.set(
+                TelephonyMonitorPreferenceController.BUILD_TYPE, "user");
+
+        assertThat(mController.isAvailable()).isFalse();
+    }
+
+    @Config(shadows = {SettingsShadowSystemProperties.class})
+    @Test
+    public void isAvailable_falseShowFlagWithUserdebugBuild_shouldReturnFalse() {
+        when(mContext.getResources().getBoolean(R.bool.config_show_telephony_monitor))
+                .thenReturn(false);
+        SettingsShadowSystemProperties.set(
+                TelephonyMonitorPreferenceController.BUILD_TYPE, "userdebug");
+
+        assertThat(mController.isAvailable()).isFalse();
+    }
+
+    @Config(shadows = {SettingsShadowSystemProperties.class})
+    @Test
+    public void isAvailable_falseShowFlagWithEngBuild_shouldReturnFalse() {
+        when(mContext.getResources().getBoolean(R.bool.config_show_telephony_monitor))
+                .thenReturn(false);
+        SettingsShadowSystemProperties.set(
+                TelephonyMonitorPreferenceController.BUILD_TYPE, "eng");
+
+        assertThat(mController.isAvailable()).isFalse();
+    }
+
+    @Config(shadows = {SettingsShadowSystemProperties.class})
+    @Test
+    public void isAvailable_falseShowFlagWithUserBuild_shouldReturnFalse() {
+        when(mContext.getResources().getBoolean(R.bool.config_show_telephony_monitor))
+                .thenReturn(false);
+        SettingsShadowSystemProperties.set(
+                TelephonyMonitorPreferenceController.BUILD_TYPE, "user");
+
+        assertThat(mController.isAvailable()).isFalse();
+    }
+
+    @Config(shadows = {SettingsShadowSystemProperties.class})
+    @Test
+    public void displayPreference_telephonyMonitorEnabled_shouldCheckedPreference() {
+        when(mContext.getResources().getBoolean(R.bool.config_show_telephony_monitor))
+                .thenReturn(true);
+        SettingsShadowSystemProperties.set(
+                TelephonyMonitorPreferenceController.PROPERTY_TELEPHONY_MONITOR, "true");
+        SettingsShadowSystemProperties.set(
+                TelephonyMonitorPreferenceController.BUILD_TYPE, "userdebug");
+
+        mController.displayPreference(mScreen);
+
+        verify(mPreference).setChecked(true);
+    }
+
+    @Config(shadows = {SettingsShadowSystemProperties.class})
+    @Test
+    public void displayPreference_telephonyMonitorDisabled_shouldUncheckedPreference() {
+        when(mContext.getResources().getBoolean(R.bool.config_show_telephony_monitor))
+                .thenReturn(true);
+        SettingsShadowSystemProperties.set(
+                TelephonyMonitorPreferenceController.PROPERTY_TELEPHONY_MONITOR, "false");
+        SettingsShadowSystemProperties.set(
+                TelephonyMonitorPreferenceController.BUILD_TYPE, "userdebug");
+
+        mController.displayPreference(mScreen);
+
+        verify(mPreference).setChecked(false);
+    }
+
+    @Config(shadows = {SettingsShadowSystemProperties.class})
+    @Test
+    public void handlePreferenceTreeClick_preferenceChecked_shouldEnableTelephonyMonitor() {
+        when(mPreference.isChecked()).thenReturn(true);
+
+        when(mContext.getResources().getString(R.string.telephony_monitor_toast))
+                .thenReturn("To apply telephony monitor change, reboot device");
+
+        mController.handlePreferenceTreeClick(mPreference);
+
+        assertThat(SystemProperties.getBoolean(
+                TelephonyMonitorPreferenceController.PROPERTY_TELEPHONY_MONITOR, false)).isTrue();
+    }
+
+    @Config(shadows = {SettingsShadowSystemProperties.class})
+    @Test
+    public void handlePreferenceTreeClick_preferenceUnchecked_shouldDisableTelephonyMonitor() {
+        when(mPreference.isChecked()).thenReturn(false);
+
+        when(mContext.getResources().getString(R.string.telephony_monitor_toast))
+                .thenReturn("To apply telephony monitor change, reboot device");
+
+        mController.handlePreferenceTreeClick(mPreference);
+
+        assertThat(SystemProperties.getBoolean(
+                TelephonyMonitorPreferenceController.PROPERTY_TELEPHONY_MONITOR, false)).isFalse();
+    }
+
+}
diff --git a/tests/robotests/src/com/android/settings/testutils/shadow/SettingsShadowSystemProperties.java b/tests/robotests/src/com/android/settings/testutils/shadow/SettingsShadowSystemProperties.java
index b5ef06a..45eb432 100644
--- a/tests/robotests/src/com/android/settings/testutils/shadow/SettingsShadowSystemProperties.java
+++ b/tests/robotests/src/com/android/settings/testutils/shadow/SettingsShadowSystemProperties.java
@@ -55,7 +55,6 @@
         sValues.put(key, val);
     }
 
-
     @Implementation
     public static String get(String key, String def) {
         String value = sValues.get(key);