diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 06de6c2a3..93c982f89 100755
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -47,7 +47,6 @@
     <uses-permission android:name="android.permission.KILL_BACKGROUND_PROCESSES" />
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
 
-    <uses-feature android:name="android.hardware.camera.autofocus" />
     <supports-screens
         android:anyDensity="true"
         android:largeScreens="true"
diff --git a/app/src/main/java/org/linphone/assistant/AssistantActivity.java b/app/src/main/java/org/linphone/assistant/AssistantActivity.java
index 136ef1346..3a5abd26b 100644
--- a/app/src/main/java/org/linphone/assistant/AssistantActivity.java
+++ b/app/src/main/java/org/linphone/assistant/AssistantActivity.java
@@ -87,7 +87,6 @@ public class AssistantActivity extends Activity
                 AccountCreatorListener {
     private static final int PERMISSIONS_REQUEST_RECORD_AUDIO = 201;
     private static final int PERMISSIONS_REQUEST_CAMERA = 202;
-    private static final int PERMISSIONS_ENABLED_CAMERA = 203;
     private static AssistantActivity instance;
     public DialPlan country;
     public String phone_number;
@@ -399,17 +398,11 @@ public class AssistantActivity extends Activity
                 }
                 break;
             case PERMISSIONS_REQUEST_RECORD_AUDIO:
-                LinphoneUtils.dispatchOnUIThread(
-                        new Runnable() {
-                            @Override
-                            public void run() {
-                                if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
-                                    launchEchoCancellerCalibration(true);
-                                } else {
-                                    isEchoCalibrationFinished();
-                                }
-                            }
-                        });
+                if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
+                    launchEchoCancellerCalibration(true);
+                } else {
+                    isEchoCalibrationFinished();
+                }
                 break;
         }
     }
@@ -581,7 +574,7 @@ public class AssistantActivity extends Activity
                 != PackageManager.PERMISSION_GRANTED) {
             checkAndRequestVideoPermission();
         } else {
-            fragment = new QrcodeFragment();
+            fragment = new QrCodeFragment();
             changeFragment(fragment);
             currentFragment = AssistantFragmentsEnum.QRCODE_READER;
             back.setVisibility(View.VISIBLE);
diff --git a/app/src/main/java/org/linphone/assistant/QrcodeFragment.java b/app/src/main/java/org/linphone/assistant/QrCodeFragment.java
similarity index 93%
rename from app/src/main/java/org/linphone/assistant/QrcodeFragment.java
rename to app/src/main/java/org/linphone/assistant/QrCodeFragment.java
index bde210261..0862d5e6a 100644
--- a/app/src/main/java/org/linphone/assistant/QrcodeFragment.java
+++ b/app/src/main/java/org/linphone/assistant/QrCodeFragment.java
@@ -1,7 +1,7 @@
 package org.linphone.assistant;
 
 /*
-QrcodeFragment.java
+QrCodeFragment.java
 Copyright (C) 2018  Belledonne Communications, Grenoble, France
 
 This program is free software; you can redistribute it and/or
@@ -31,7 +31,7 @@ import org.linphone.core.Core;
 import org.linphone.core.CoreListenerStub;
 import org.linphone.mediastream.video.capture.hwconf.AndroidCameraConfiguration;
 
-public class QrcodeFragment extends Fragment {
+public class QrCodeFragment extends Fragment {
     private TextureView mQrcodeView;
     private CoreListenerStub mListener;
 
@@ -84,11 +84,6 @@ public class QrcodeFragment extends Fragment {
         enableQrcodeReader(true);
     }
 
-    @Override
-    public void onStart() {
-        super.onStart();
-    }
-
     @Override
     public void onResume() {
         launchQrcodeReader();
@@ -101,9 +96,4 @@ public class QrcodeFragment extends Fragment {
         // setBackCamera(false);
         super.onPause();
     }
-
-    @Override
-    public void onDestroy() {
-        super.onDestroy();
-    }
 }
diff --git a/app/src/main/java/org/linphone/assistant/RemoteProvisioningFragment.java b/app/src/main/java/org/linphone/assistant/RemoteProvisioningFragment.java
index b7f45fac8..e710ac213 100644
--- a/app/src/main/java/org/linphone/assistant/RemoteProvisioningFragment.java
+++ b/app/src/main/java/org/linphone/assistant/RemoteProvisioningFragment.java
@@ -33,24 +33,24 @@ import org.linphone.R;
 import org.linphone.settings.LinphonePreferences;
 
 public class RemoteProvisioningFragment extends Fragment implements OnClickListener, TextWatcher {
-    private EditText remoteProvisioningUrl;
-    private Button apply, qrcode;
+    private EditText mRemoteProvisioningUrl;
+    private Button mApply, mQrcode;
 
     @Override
     public View onCreateView(
             LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.assistant_remote_provisioning, container, false);
 
-        remoteProvisioningUrl = view.findViewById(R.id.assistant_remote_provisioning_url);
-        remoteProvisioningUrl.addTextChangedListener(this);
-        qrcode = view.findViewById(R.id.assistant_qrcode);
-        qrcode.setOnClickListener(this);
-        apply = view.findViewById(R.id.assistant_apply);
-        apply.setEnabled(false);
-        apply.setOnClickListener(this);
+        mRemoteProvisioningUrl = view.findViewById(R.id.assistant_remote_provisioning_url);
+        mRemoteProvisioningUrl.addTextChangedListener(this);
+        mQrcode = view.findViewById(R.id.assistant_qrcode);
+        mQrcode.setOnClickListener(this);
+        mApply = view.findViewById(R.id.assistant_apply);
+        mApply.setEnabled(false);
+        mApply.setOnClickListener(this);
 
-        if (!getArguments().getString("RemoteUrl").isEmpty()) {
-            remoteProvisioningUrl.setText(getArguments().getString("RemoteUrl"));
+        if (getArguments() != null && !getArguments().getString("RemoteUrl").isEmpty()) {
+            mRemoteProvisioningUrl.setText(getArguments().getString("RemoteUrl"));
         }
 
         return view;
@@ -61,7 +61,7 @@ public class RemoteProvisioningFragment extends Fragment implements OnClickListe
         int id = v.getId();
 
         if (id == R.id.assistant_apply) {
-            String url = remoteProvisioningUrl.getText().toString();
+            String url = mRemoteProvisioningUrl.getText().toString();
             AssistantActivity.instance().displayRemoteProvisioningInProgressDialog();
             LinphonePreferences.instance().setRemoteProvisioningUrl(url);
             LinphoneManager.getLc().getConfig().sync();
@@ -77,7 +77,7 @@ public class RemoteProvisioningFragment extends Fragment implements OnClickListe
 
     @Override
     public void onTextChanged(CharSequence s, int start, int before, int count) {
-        apply.setEnabled(!remoteProvisioningUrl.getText().toString().isEmpty());
+        mApply.setEnabled(!mRemoteProvisioningUrl.getText().toString().isEmpty());
     }
 
     @Override