diff --git a/src/com/android/settings/development/AllowAppsOnExternalPreferenceController.java b/src/com/android/settings/development/AllowAppsOnExternalPreferenceController.java
new file mode 100644
index 00000000000..fb6945553ee
--- /dev/null
+++ b/src/com/android/settings/development/AllowAppsOnExternalPreferenceController.java
@@ -0,0 +1,83 @@
+/*
+ * 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.provider.Settings;
+import android.support.annotation.VisibleForTesting;
+import android.support.v14.preference.SwitchPreference;
+import android.support.v7.preference.Preference;
+import android.support.v7.preference.PreferenceScreen;
+
+public class AllowAppsOnExternalPreferenceController extends
+        DeveloperOptionsPreferenceController implements Preference.OnPreferenceChangeListener {
+
+    private static final String FORCE_ALLOW_ON_EXTERNAL_KEY = "force_allow_on_external";
+
+    @VisibleForTesting
+    static final int SETTING_VALUE_OFF = 0;
+    @VisibleForTesting
+    static final int SETTING_VALUE_ON = 1;
+
+    private SwitchPreference mPreference;
+
+    public AllowAppsOnExternalPreferenceController(Context context) {
+        super(context);
+    }
+
+    @Override
+    public String getPreferenceKey() {
+        return FORCE_ALLOW_ON_EXTERNAL_KEY;
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+
+        mPreference = (SwitchPreference) screen.findPreference(getPreferenceKey());
+    }
+
+    @Override
+    public boolean onPreferenceChange(Preference preference, Object newValue) {
+        final boolean isEnabled = (Boolean) newValue;
+        Settings.Global.putInt(mContext.getContentResolver(),
+                Settings.Global.FORCE_ALLOW_ON_EXTERNAL,
+                isEnabled ? SETTING_VALUE_ON : SETTING_VALUE_OFF);
+        return true;
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        final int mode = Settings.Global.getInt(mContext.getContentResolver(),
+                Settings.Global.FORCE_ALLOW_ON_EXTERNAL, SETTING_VALUE_OFF);
+
+        mPreference.setChecked(mode != SETTING_VALUE_OFF);
+    }
+
+    @Override
+    protected void onDeveloperOptionsSwitchEnabled() {
+        mPreference.setEnabled(true);
+    }
+
+    @Override
+    protected void onDeveloperOptionsSwitchDisabled() {
+        Settings.Global.putInt(mContext.getContentResolver(),
+                Settings.Global.FORCE_ALLOW_ON_EXTERNAL, SETTING_VALUE_OFF);
+        mPreference.setEnabled(false);
+        mPreference.setChecked(false);
+    }
+}
diff --git a/src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java b/src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java
index 96bd4c1bc30..91b8b225e0a 100644
--- a/src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java
+++ b/src/com/android/settings/development/DevelopmentSettingsDashboardFragment.java
@@ -310,7 +310,7 @@ public class DevelopmentSettingsDashboardFragment extends RestrictedDashboardFra
         controllers.add(new AppsNotRespondingPreferenceController(context));
         // show notification channel warnings
         // inactive apps
-        // force allow apps on external
+        controllers.add(new AllowAppsOnExternalPreferenceController(context));
         // force activities to be resizable
         // reset shortcutmanager rate-limiting
         return controllers;
diff --git a/tests/robotests/src/com/android/settings/development/AllowAppsOnExternalPreferenceControllerTest.java b/tests/robotests/src/com/android/settings/development/AllowAppsOnExternalPreferenceControllerTest.java
new file mode 100644
index 00000000000..e23c4cc937a
--- /dev/null
+++ b/tests/robotests/src/com/android/settings/development/AllowAppsOnExternalPreferenceControllerTest.java
@@ -0,0 +1,124 @@
+/*
+ * 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 static com.android.settings.development.AllowAppsOnExternalPreferenceController
+        .SETTING_VALUE_OFF;
+import static com.android.settings.development.AllowAppsOnExternalPreferenceController
+        .SETTING_VALUE_ON;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.content.Context;
+import android.provider.Settings;
+import android.support.v14.preference.SwitchPreference;
+import android.support.v7.preference.PreferenceScreen;
+
+import com.android.settings.TestConfig;
+import com.android.settings.testutils.SettingsRobolectricTestRunner;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.RuntimeEnvironment;
+import org.robolectric.annotation.Config;
+
+@RunWith(SettingsRobolectricTestRunner.class)
+@Config(manifest = TestConfig.MANIFEST_PATH, sdk = TestConfig.SDK_VERSION)
+public class AllowAppsOnExternalPreferenceControllerTest {
+
+    @Mock
+    private SwitchPreference mPreference;
+    @Mock
+    private PreferenceScreen mPreferenceScreen;
+
+    private Context mContext;
+    private AllowAppsOnExternalPreferenceController mController;
+
+    @Before
+    public void setup() {
+        MockitoAnnotations.initMocks(this);
+        mContext = RuntimeEnvironment.application;
+        mController = new AllowAppsOnExternalPreferenceController(mContext);
+        when(mPreferenceScreen.findPreference(mController.getPreferenceKey())).thenReturn(
+                mPreference);
+        mController.displayPreference(mPreferenceScreen);
+    }
+
+    @Test
+    public void onPreferenceChange_settingEnabled_allowAppsOnExternalShouldBeOn() {
+        mController.onPreferenceChange(mPreference, true /* new value */);
+
+        final int mode = Settings.Global.getInt(mContext.getContentResolver(),
+                Settings.Global.FORCE_ALLOW_ON_EXTERNAL, -1 /* default */);
+
+        assertThat(mode).isEqualTo(SETTING_VALUE_ON);
+    }
+
+    @Test
+    public void onPreferenceChange_settingDisabled_allowAppsOnExternalShouldBeOff() {
+        mController.onPreferenceChange(mPreference, false /* new value */);
+
+        final int mode = Settings.Global.getInt(mContext.getContentResolver(),
+                Settings.Global.FORCE_ALLOW_ON_EXTERNAL, -1 /* default */);
+
+        assertThat(mode).isEqualTo(SETTING_VALUE_OFF);
+    }
+
+    @Test
+    public void updateState_settingDisabled_preferenceShouldNotBeChecked() {
+        Settings.Global.putInt(mContext.getContentResolver(),
+                Settings.Global.FORCE_ALLOW_ON_EXTERNAL, SETTING_VALUE_OFF);
+        mController.updateState(mPreference);
+
+        verify(mPreference).setChecked(false);
+    }
+
+    @Test
+    public void updateState_settingEnabled_preferenceShouldBeChecked() {
+        Settings.Global.putInt(mContext.getContentResolver(),
+                Settings.Global.FORCE_ALLOW_ON_EXTERNAL, SETTING_VALUE_ON);
+        mController.updateState(mPreference);
+
+        verify(mPreference).setChecked(true);
+    }
+
+    @Test
+    public void onDeveloperOptionsSwitchDisabled_shouldDisablePreference() {
+        mController.onDeveloperOptionsSwitchDisabled();
+
+        final int mode = Settings.Global.getInt(mContext.getContentResolver(),
+                Settings.Global.FORCE_ALLOW_ON_EXTERNAL, -1 /* default */);
+
+        assertThat(mode).isEqualTo(SETTING_VALUE_OFF);
+        verify(mPreference).setChecked(false);
+        verify(mPreference).setEnabled(false);
+    }
+
+    @Test
+    public void onDeveloperOptionsSwitchEnabled_shouldEnablePreference() {
+        mController.onDeveloperOptionsSwitchEnabled();
+
+        verify(mPreference).setEnabled(true);
+    }
+}