diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index c078dde..bd59451 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -25,6 +25,7 @@
         android:theme="@style/RecThemeLight">
         <service android:name=".services.RecordingService" />
         <service android:name=".services.EncodingService" />
+        <service android:name=".services.ControlsService" />
         <service
             android:name=".services.TileService"
             android:icon="@drawable/ic_mic_24dp"
diff --git a/app/src/main/java/com/github/axet/audiorecorder/activities/MainActivity.java b/app/src/main/java/com/github/axet/audiorecorder/activities/MainActivity.java
index f27bc06..cbc1838 100644
--- a/app/src/main/java/com/github/axet/audiorecorder/activities/MainActivity.java
+++ b/app/src/main/java/com/github/axet/audiorecorder/activities/MainActivity.java
@@ -46,6 +46,7 @@ import com.github.axet.audiorecorder.app.AudioApplication;
 import com.github.axet.audiorecorder.app.EncodingStorage;
 import com.github.axet.audiorecorder.app.Recordings;
 import com.github.axet.audiorecorder.app.Storage;
+import com.github.axet.audiorecorder.services.ControlsService;
 import com.github.axet.audiorecorder.services.EncodingService;
 import com.github.axet.audiorecorder.services.RecordingService;
 
@@ -466,6 +467,7 @@ public class MainActivity extends AppCompatThemeActivity {
 
         RecordingService.startIfPending(this);
         EncodingService.startIfPending(this);
+        ControlsService.startIfEnabled(this);
 
         try {
             new Recordings.ExoLoader(this, false);
diff --git a/app/src/main/java/com/github/axet/audiorecorder/activities/RecordingActivity.java b/app/src/main/java/com/github/axet/audiorecorder/activities/RecordingActivity.java
index 2a62621..5a98b6f 100644
--- a/app/src/main/java/com/github/axet/audiorecorder/activities/RecordingActivity.java
+++ b/app/src/main/java/com/github/axet/audiorecorder/activities/RecordingActivity.java
@@ -52,6 +52,7 @@ import com.github.axet.audiorecorder.app.AudioApplication;
 import com.github.axet.audiorecorder.app.RecordingStorage;
 import com.github.axet.audiorecorder.app.Storage;
 import com.github.axet.audiorecorder.services.BluetoothReceiver;
+import com.github.axet.audiorecorder.services.ControlsService;
 import com.github.axet.audiorecorder.services.EncodingService;
 import com.github.axet.audiorecorder.services.RecordingService;
 
@@ -906,6 +907,7 @@ public class RecordingActivity extends AppCompatThemeActivity {
         }
 
         RecordingService.stopRecording(this);
+        ControlsService.startIfEnabled(this);
 
         if (pscl != null) {
             TelephonyManager tm = (TelephonyManager) this.getSystemService(Context.TELEPHONY_SERVICE);
@@ -941,6 +943,7 @@ public class RecordingActivity extends AppCompatThemeActivity {
             recording.startRecording();
 
             RecordingService.startService(this, Storage.getName(this, recording.targetUri), true, duration);
+            ControlsService.hideIcon(this);
         } catch (RuntimeException e) {
             Toast.Error(RecordingActivity.this, e);
             finish();
diff --git a/app/src/main/java/com/github/axet/audiorecorder/activities/SettingsActivity.java b/app/src/main/java/com/github/axet/audiorecorder/activities/SettingsActivity.java
index 94c50de..8308e9c 100644
--- a/app/src/main/java/com/github/axet/audiorecorder/activities/SettingsActivity.java
+++ b/app/src/main/java/com/github/axet/audiorecorder/activities/SettingsActivity.java
@@ -29,6 +29,7 @@ import com.github.axet.audiolibrary.widgets.RecordingVolumePreference;
 import com.github.axet.audiorecorder.R;
 import com.github.axet.audiorecorder.app.AudioApplication;
 import com.github.axet.audiorecorder.app.Storage;
+import com.github.axet.audiorecorder.services.ControlsService;
 import com.github.axet.audiorecorder.services.RecordingService;
 
 import java.lang.reflect.Array;
@@ -98,9 +99,9 @@ public class SettingsActivity extends AppCompatSettingsThemeActivity implements
         super.onSharedPreferenceChanged(sharedPreferences, key);
         if (key.equals(AudioApplication.PREFERENCE_CONTROLS)) {
             if (sharedPreferences.getBoolean(AudioApplication.PREFERENCE_CONTROLS, false))
-                RecordingService.start(this);
+                ControlsService.start(this);
             else
-                RecordingService.stop(this);
+                ControlsService.stop(this);
         }
         if (key.equals(AudioApplication.PREFERENCE_STORAGE))
             storage.migrateLocalStorageDialog(this);
@@ -249,6 +250,9 @@ public class SettingsActivity extends AppCompatSettingsThemeActivity implements
             super.onResume();
             SilencePreferenceCompat silent = (SilencePreferenceCompat) findPreference(AudioApplication.PREFERENCE_SILENT);
             silent.onResume();
+            Preference controls = findPreference(AudioApplication.PREFERENCE_CONTROLS);
+            if (Build.VERSION.SDK_INT < 21)
+                controls.setVisible(false);
         }
     }
 }
diff --git a/app/src/main/java/com/github/axet/audiorecorder/app/AudioApplication.java b/app/src/main/java/com/github/axet/audiorecorder/app/AudioApplication.java
index 09f6e58..f466a44 100644
--- a/app/src/main/java/com/github/axet/audiorecorder/app/AudioApplication.java
+++ b/app/src/main/java/com/github/axet/audiorecorder/app/AudioApplication.java
@@ -32,6 +32,7 @@ public class AudioApplication extends com.github.axet.audiolibrary.app.MainAppli
     public static final String PREFERENCE_NEXT = "next";
 
     public NotificationChannelCompat channelStatus;
+    public NotificationChannelCompat channelPersistent;
     public RecordingStorage recording;
     public EncodingStorage encodings;
 
@@ -45,6 +46,7 @@ public class AudioApplication extends com.github.axet.audiolibrary.app.MainAppli
         Log.d(TAG, "onCreate");
 
         channelStatus = new NotificationChannelCompat(this, "status", "Status", NotificationManagerCompat.IMPORTANCE_LOW);
+        channelPersistent = new NotificationChannelCompat(this, "persistent", "Persistent", NotificationManagerCompat.IMPORTANCE_LOW);
         encodings = new EncodingStorage(this);
 
         switch (getVersion(PREFERENCE_VERSION, R.xml.pref_general)) {
diff --git a/app/src/main/java/com/github/axet/audiorecorder/services/ControlsService.java b/app/src/main/java/com/github/axet/audiorecorder/services/ControlsService.java
new file mode 100644
index 0000000..5738be4
--- /dev/null
+++ b/app/src/main/java/com/github/axet/audiorecorder/services/ControlsService.java
@@ -0,0 +1,236 @@
+package com.github.axet.audiorecorder.services;
+
+import android.annotation.SuppressLint;
+import android.app.KeyguardManager;
+import android.app.Notification;
+import android.app.PendingIntent;
+import android.app.Service;
+import android.content.ContentResolver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.SharedPreferences;
+import android.net.Uri;
+import android.os.Build;
+import android.os.PowerManager;
+import android.preference.PreferenceManager;
+import android.util.Log;
+import android.view.Display;
+import android.view.View;
+import android.view.WindowManager;
+import android.widget.RemoteViews;
+
+import com.github.axet.androidlibrary.app.AlarmManager;
+import com.github.axet.androidlibrary.app.ProximityShader;
+import com.github.axet.androidlibrary.preferences.OptimizationPreferenceCompat;
+import com.github.axet.androidlibrary.services.PersistentService;
+import com.github.axet.androidlibrary.widgets.NotificationChannelCompat;
+import com.github.axet.androidlibrary.widgets.RemoteNotificationCompat;
+import com.github.axet.androidlibrary.widgets.RemoteViewsCompat;
+import com.github.axet.audiolibrary.app.Storage;
+import com.github.axet.audiorecorder.R;
+import com.github.axet.audiorecorder.activities.MainActivity;
+import com.github.axet.audiorecorder.activities.RecordingActivity;
+import com.github.axet.audiorecorder.app.AudioApplication;
+
+import java.io.File;
+
+public class ControlsService extends PersistentService {
+    public static final String TAG = ControlsService.class.getSimpleName();
+
+    public static final int NOTIFICATION_CONTROLS_ICON = 3;
+    public static final int NOTIFICATION_PERSISTENT_ICON = 4;
+
+    Storage storage;
+    OptimizationPreferenceCompat.NotificationIcon controls;
+
+    public static String SHOW_ACTIVITY = ControlsService.class.getCanonicalName() + ".SHOW_ACTIVITY";
+    public static String RECORD_BUTTON = ControlsService.class.getCanonicalName() + ".RECORD_BUTTON";
+    public static String HIDE_ICON = ControlsService.class.getCanonicalName() + ".HIDE_ICON";
+
+    public static void startIfEnabled(Context context) { // notification controls enabled?
+        SharedPreferences shared = PreferenceManager.getDefaultSharedPreferences(context);
+        if (!shared.getBoolean(AudioApplication.PREFERENCE_CONTROLS, false))
+            return;
+        start(context);
+    }
+
+    public static void start(Context context) { // start persistent icon service
+        start(context, new Intent(context, ControlsService.class));
+    }
+
+    public static void stop(Context context) {
+        stop(context, new Intent(context, ControlsService.class));
+    }
+
+    public static void hideIcon(Context context) {
+        SharedPreferences shared = PreferenceManager.getDefaultSharedPreferences(context);
+        if (!shared.getBoolean(AudioApplication.PREFERENCE_CONTROLS, false))
+            return;
+        start(context, new Intent(context, ControlsService.class).setAction(HIDE_ICON));
+    }
+
+    public ControlsService() {
+    }
+
+    @Override
+    public void onCreate() {
+        super.onCreate();
+    }
+
+    @Override
+    public void onCreateOptimization() {
+        storage = new Storage(this);
+        optimization = new OptimizationPreferenceCompat.ServiceReceiver(this, NOTIFICATION_PERSISTENT_ICON, null, AudioApplication.PREFERENCE_NEXT) {
+            @Override
+            public void onCreateIcon(Service service, int id) {
+                controls = new OptimizationPreferenceCompat.NotificationIcon(ControlsService.this, NOTIFICATION_CONTROLS_ICON) {
+                    @Override
+                    public void updateIcon(Intent intent) {
+                        KeyguardManager myKM = (KeyguardManager) getSystemService(Context.KEYGUARD_SERVICE);
+                        if (myKM.inKeyguardRestrictedInputMode() && !storage.recordingPending())
+                            intent = new Intent();
+                        else
+                            intent = null;
+                        super.updateIcon(intent);
+                    }
+
+                    @Override
+                    public Notification build(Intent intent) {
+                        PendingIntent main;
+
+                        RemoteNotificationCompat.Builder builder;
+
+                        String title;
+                        String text;
+
+                        title = getString(R.string.app_name);
+                        Uri f = storage.getStoragePath();
+                        long free = Storage.getFree(context, f);
+                        long sec = Storage.average(context, free);
+                        text = AudioApplication.formatFree(context, free, sec);
+                        builder = new RemoteNotificationCompat.Low(context, R.layout.notifictaion);
+                        builder.setViewVisibility(R.id.notification_record, View.VISIBLE);
+                        builder.setViewVisibility(R.id.notification_pause, View.GONE);
+                        main = PendingIntent.getActivity(context, 0, new Intent(context, MainActivity.class), PendingIntent.FLAG_UPDATE_CURRENT);
+
+                        PendingIntent re = PendingIntent.getService(context, 0,
+                                new Intent(context, ControlsService.class).setAction(RECORD_BUTTON),
+                                PendingIntent.FLAG_UPDATE_CURRENT);
+
+                        builder.setOnClickPendingIntent(R.id.notification_record, re);
+
+                        builder.setTheme(AudioApplication.getTheme(context, R.style.RecThemeLight, R.style.RecThemeDark))
+                                .setChannel(AudioApplication.from(context).channelStatus)
+                                .setImageViewTint(R.id.icon_circle, builder.getThemeColor(R.attr.colorButtonNormal))
+                                .setTitle(title)
+                                .setText(text)
+                                .setWhen(controls.notification)
+                                .setMainIntent(main)
+                                .setAdaptiveIcon(R.drawable.ic_launcher_foreground)
+                                .setSmallIcon(R.drawable.ic_launcher_notification)
+                                .setOngoing(true);
+
+                        return builder.build();
+                    }
+
+                    @Override
+                    public boolean isOptimization() {
+                        return false;
+                    }
+                };
+                controls.create();
+                icon = new OptimizationPreferenceCompat.OptimizationIcon(service, id, key) {
+                    @Override
+                    public void updateIcon(Intent intent) {
+                        super.updateIcon(intent);
+                    }
+
+                    @SuppressLint("RestrictedApi")
+                    public Notification build(Intent intent) {
+                        PendingIntent main;
+
+                        RemoteNotificationCompat.Builder builder;
+
+                        String title;
+                        String text;
+
+                        title = getString(R.string.app_name);
+                        text = "Persistent Controls Icon";
+                        builder = new RemoteNotificationCompat.Low(context, R.layout.notifictaion);
+                        builder.setViewVisibility(R.id.notification_record, View.GONE);
+                        builder.setViewVisibility(R.id.notification_pause, View.GONE);
+                        main = PendingIntent.getActivity(context, 0, new Intent(context, MainActivity.class), PendingIntent.FLAG_UPDATE_CURRENT);
+
+                        builder.setTheme(AudioApplication.getTheme(context, R.style.RecThemeLight, R.style.RecThemeDark))
+                                .setChannel(AudioApplication.from(context).channelPersistent)
+                                .setImageViewTint(R.id.icon_circle, builder.getThemeColor(R.attr.colorButtonNormal))
+                                .setTitle(title)
+                                .setText(text)
+                                .setWhen(icon.notification)
+                                .setMainIntent(main)
+                                .setAdaptiveIcon(R.drawable.ic_launcher_foreground)
+                                .setSmallIcon(R.drawable.ic_launcher_notification)
+                                .setOngoing(true);
+
+                        return builder.build();
+                    }
+                };
+                icon.create();
+            }
+
+            @Override
+            public void updateIcon() {
+                super.updateIcon();
+                controls.updateIcon(null);
+            }
+
+            @Override
+            public boolean isOptimization() {
+                return true; // we not using optimization preference
+            }
+
+            @Override
+            public void onReceive(Context context, Intent intent) {
+                super.onReceive(context, intent);
+                String a = intent.getAction();
+                if (a == null)
+                    return;
+                switch (a) {
+                    case Intent.ACTION_USER_PRESENT:
+                        optimization.updateIcon();
+                        break;
+                    case Intent.ACTION_SCREEN_ON:
+                        optimization.updateIcon();
+                        break;
+                    case Intent.ACTION_SCREEN_OFF:
+                        optimization.updateIcon();
+                        break;
+                }
+            }
+        };
+        optimization.filters.addAction(Intent.ACTION_USER_PRESENT);
+        optimization.filters.addAction(Intent.ACTION_SCREEN_ON);
+        optimization.filters.addAction(Intent.ACTION_SCREEN_OFF);
+        optimization.create();
+    }
+
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+    }
+
+    @Override
+    public void onStartCommand(Intent intent) {
+        String a = intent.getAction();
+        if (a == null) {
+            optimization.updateIcon();
+        } else if (a.equals(HIDE_ICON)) {
+            controls.hideIcon();
+        } else if (a.equals(RECORD_BUTTON)) {
+            RecordingActivity.startActivity(this, false);
+        } else if (a.equals(SHOW_ACTIVITY)) {
+            ProximityShader.closeSystemDialogs(this);
+            MainActivity.startActivity(this);
+        }
+    }
+}
diff --git a/app/src/main/java/com/github/axet/audiorecorder/services/OnBootReceiver.java b/app/src/main/java/com/github/axet/audiorecorder/services/OnBootReceiver.java
index e10fbd7..7b68817 100644
--- a/app/src/main/java/com/github/axet/audiorecorder/services/OnBootReceiver.java
+++ b/app/src/main/java/com/github/axet/audiorecorder/services/OnBootReceiver.java
@@ -13,5 +13,6 @@ public class OnBootReceiver extends BroadcastReceiver {
         Log.d(TAG, "onReceive");
         RecordingService.startIfPending(context);
         EncodingService.startIfPending(context);
+        ControlsService.startIfEnabled(context);
     }
 }
diff --git a/app/src/main/java/com/github/axet/audiorecorder/services/OnExternalReceiver.java b/app/src/main/java/com/github/axet/audiorecorder/services/OnExternalReceiver.java
index 64910ff..9368e77 100644
--- a/app/src/main/java/com/github/axet/audiorecorder/services/OnExternalReceiver.java
+++ b/app/src/main/java/com/github/axet/audiorecorder/services/OnExternalReceiver.java
@@ -30,5 +30,6 @@ public class OnExternalReceiver extends BroadcastReceiver {
             return;
 
         RecordingService.startIfPending(context);
+        ControlsService.startIfEnabled(context);
     }
 }
diff --git a/app/src/main/java/com/github/axet/audiorecorder/services/OnUpgradeReceiver.java b/app/src/main/java/com/github/axet/audiorecorder/services/OnUpgradeReceiver.java
index 83bd360..27c2116 100644
--- a/app/src/main/java/com/github/axet/audiorecorder/services/OnUpgradeReceiver.java
+++ b/app/src/main/java/com/github/axet/audiorecorder/services/OnUpgradeReceiver.java
@@ -15,5 +15,6 @@ public class OnUpgradeReceiver extends BroadcastReceiver {
     public void onReceive(Context context, Intent intent) {
         Log.d(TAG, "onReceive");
         RecordingService.startIfPending(context);
+        ControlsService.startIfEnabled(context);
     }
 }
diff --git a/app/src/main/java/com/github/axet/audiorecorder/services/RecordingService.java b/app/src/main/java/com/github/axet/audiorecorder/services/RecordingService.java
index 0689b00..58211e7 100644
--- a/app/src/main/java/com/github/axet/audiorecorder/services/RecordingService.java
+++ b/app/src/main/java/com/github/axet/audiorecorder/services/RecordingService.java
@@ -48,13 +48,6 @@ public class RecordingService extends PersistentService {
 
     Storage storage; // for storage path
 
-    public static void startIfEnabled(Context context) { // notification controls enabled?
-        SharedPreferences shared = PreferenceManager.getDefaultSharedPreferences(context);
-        if (!shared.getBoolean(AudioApplication.PREFERENCE_CONTROLS, false))
-            return;
-        start(context);
-    }
-
     public static void startIfPending(Context context) { // if recording pending or controls enabled
         Storage storage = new Storage(context);
         if (storage.recordingPending()) {
@@ -75,7 +68,6 @@ public class RecordingService extends PersistentService {
             startService(context, d, false, null);
             return;
         }
-        startIfEnabled(context);
     }
 
     public static void start(Context context) { // start persistent icon service
@@ -91,11 +83,6 @@ public class RecordingService extends PersistentService {
     }
 
     public static void stopRecording(Context context) {
-        SharedPreferences shared = PreferenceManager.getDefaultSharedPreferences(context);
-        if (shared.getBoolean(AudioApplication.PREFERENCE_CONTROLS, false)) {
-            start(context);
-            return;
-        }
         stop(context);
     }
 
@@ -115,7 +102,7 @@ public class RecordingService extends PersistentService {
     public void onCreateOptimization() {
         storage = new Storage(this);
         optimization = new OptimizationPreferenceCompat.ServiceReceiver(this, NOTIFICATION_RECORDING_ICON, null, AudioApplication.PREFERENCE_NEXT) {
-            Intent notificationIntent;
+            Intent notificationIntent; // speed up, update notification text without calling notify()
 
             @Override
             public void onCreateIcon(Service service, int id) {
@@ -144,48 +131,36 @@ public class RecordingService extends PersistentService {
 
                         String title;
                         String text;
-                        if (targetFile == null) {  // buildPersistentIcon();
-                            title = getString(R.string.app_name);
-                            Uri f = storage.getStoragePath();
-                            long free = Storage.getFree(context, f);
-                            long sec = Storage.average(context, free);
-                            text = AudioApplication.formatFree(context, free, sec);
-                            builder = new RemoteNotificationCompat.Low(context, R.layout.notifictaion);
-                            builder.setViewVisibility(R.id.notification_record, View.VISIBLE);
-                            builder.setViewVisibility(R.id.notification_pause, View.GONE);
-                            main = PendingIntent.getActivity(context, 0, new Intent(context, MainActivity.class), PendingIntent.FLAG_UPDATE_CURRENT);
-                        } else { // buildRecordingIcon();
-                            if (recording)
-                                title = getString(R.string.recording_title);
-                            else
-                                title = getString(R.string.pause_title);
-                            if (duration != null) {
-                                title += " (" + duration + ")";
-                                if (recording && notificationIntent != null && notificationIntent.hasExtra("duration") && notificationIntent.getBooleanExtra("recording", false)) { // speed up
-                                    try {
-                                        RemoteViews a = new RemoteViews(getPackageName(), icon.notification.contentView.getLayoutId());
+                        if (recording)
+                            title = getString(R.string.recording_title);
+                        else
+                            title = getString(R.string.pause_title);
+                        if (duration != null) {
+                            title += " (" + duration + ")";
+                            if (recording && notificationIntent != null && notificationIntent.hasExtra("duration") && notificationIntent.getBooleanExtra("recording", false)) {
+                                try {
+                                    RemoteViews a = new RemoteViews(getPackageName(), icon.notification.contentView.getLayoutId());
+                                    a.setTextViewText(R.id.title, title);
+                                    RemoteViewsCompat.mergeRemoteViews(icon.notification.contentView, a);
+                                    if (Build.VERSION.SDK_INT >= 16 && icon.notification.bigContentView != null) {
+                                        a = new RemoteViews(getPackageName(), icon.notification.bigContentView.getLayoutId());
                                         a.setTextViewText(R.id.title, title);
-                                        RemoteViewsCompat.mergeRemoteViews(icon.notification.contentView, a);
-                                        if (Build.VERSION.SDK_INT >= 16 && icon.notification.bigContentView != null) {
-                                            a = new RemoteViews(getPackageName(), icon.notification.bigContentView.getLayoutId());
-                                            a.setTextViewText(R.id.title, title);
-                                            RemoteViewsCompat.mergeRemoteViews(icon.notification.bigContentView, a);
-                                        }
-                                        return icon.notification;
-                                    } catch (RuntimeException e) {
-                                        Log.d(TAG, "merge failed", e);
+                                        RemoteViewsCompat.mergeRemoteViews(icon.notification.bigContentView, a);
                                     }
+                                    return icon.notification;
+                                } catch (RuntimeException e) {
+                                    Log.d(TAG, "merge failed", e);
                                 }
                             }
-                            text = ".../" + targetFile;
-                            builder = new RemoteNotificationCompat.Builder(context, R.layout.notifictaion);
-                            builder.setViewVisibility(R.id.notification_record, View.GONE);
-                            builder.setViewVisibility(R.id.notification_pause, View.VISIBLE);
-                            main = PendingIntent.getService(context, 0, new Intent(context, RecordingService.class)
-                                    .setAction(SHOW_ACTIVITY)
-                                    .putExtra("targetFile", targetFile)
-                                    .putExtra("recording", recording), PendingIntent.FLAG_UPDATE_CURRENT);
                         }
+                        text = ".../" + targetFile;
+                        builder = new RemoteNotificationCompat.Builder(context, R.layout.notifictaion);
+                        builder.setViewVisibility(R.id.notification_record, View.GONE);
+                        builder.setViewVisibility(R.id.notification_pause, View.VISIBLE);
+                        main = PendingIntent.getService(context, 0, new Intent(context, RecordingService.class)
+                                .setAction(SHOW_ACTIVITY)
+                                .putExtra("targetFile", targetFile)
+                                .putExtra("recording", recording), PendingIntent.FLAG_UPDATE_CURRENT);
 
                         PendingIntent pe = PendingIntent.getService(context, 0,
                                 new Intent(context, RecordingService.class).setAction(PAUSE_BUTTON),