diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
-<manifest xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools">
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+          xmlns:tools="http://schemas.android.com/tools">
 
     <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
     <uses-permission android:name="android.permission.INTERNET"/>
@@ -9,10 +10,11 @@
     <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
     <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
     <uses-permission android:name="android.permission.READ_PHONE_STATE"/>
-    <uses-permission android:name="android.permission.POST_NOTIFICATIONS"/>
-    <!-- this is to REMOVE the permission from MQTT service -->
-    <uses-permission    tools:node="remove"
-                        android:name="android.permission.FOREGROUND_SERVICE_DATA_SYNC"/>
+    <uses-permission
+            android:name="android.permission.POST_NOTIFICATIONS"/> <!-- this is to REMOVE the permission from MQTT service -->
+    <uses-permission
+            android:name="android.permission.FOREGROUND_SERVICE_DATA_SYNC"
+            tools:node="remove"/>
 
     <queries>
         <intent>
@@ -41,6 +43,12 @@
             android:networkSecurityConfig="@xml/networks_security_config"
             android:roundIcon="@mipmap/ic_launcher_round"
             android:theme="@style/AppTheme.NoActionBar">
+        <activity
+                android:name=".ActivityBackup"
+                android:label="@string/backup_activity"
+                android:parentActivityName=".ActivityPrincipal"
+                android:theme="@style/AppTheme"
+                android:exported="false"/>
         <activity
                 android:name=".ActivityIntro"
                 android:exported="false"/>
diff --git a/app/src/main/java/it/reyboz/bustorino/ActivityBackup.kt b/app/src/main/java/it/reyboz/bustorino/ActivityBackup.kt
new file mode 100644
--- /dev/null
+++ b/app/src/main/java/it/reyboz/bustorino/ActivityBackup.kt
@@ -0,0 +1,26 @@
+package it.reyboz.bustorino
+
+import android.os.Bundle
+import it.reyboz.bustorino.fragments.BackupImportFragment
+import it.reyboz.bustorino.middleware.GeneralActivity
+
+class ActivityBackup : GeneralActivity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_container_fragment)
+
+        val actionBar = supportActionBar
+        if (actionBar != null) {
+            actionBar.setDisplayHomeAsUpEnabled(true)
+            actionBar.setIcon(R.drawable.ic_launcher)
+            actionBar.show()
+        }
+        if (savedInstanceState == null) {
+            supportFragmentManager.beginTransaction()
+                .setReorderingAllowed(true)
+                .add(R.id.fragment_container_view, BackupImportFragment::class.java, null)
+                .commit()
+        }
+    }
+
+}
\ No newline at end of file
diff --git a/app/src/main/java/it/reyboz/bustorino/ActivityExperiments.java b/app/src/main/java/it/reyboz/bustorino/ActivityExperiments.java
--- a/app/src/main/java/it/reyboz/bustorino/ActivityExperiments.java
+++ b/app/src/main/java/it/reyboz/bustorino/ActivityExperiments.java
@@ -32,7 +32,7 @@
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        setContentView(R.layout.activity_experiments);
+        setContentView(R.layout.activity_container_fragment);
 
         ActionBar actionBar = getSupportActionBar();
         if (actionBar != null) {
@@ -54,7 +54,7 @@
 
                     //.add(R.id.fragment_container_view, LinesDetailFragment.class,
                     //        LinesDetailFragment.Companion.makeArgs("gtt:4U"))
-                    .add(R.id.fragment_container_view, TestSavingFragment.class, null)
+                    .add(R.id.fragment_container_view, BackupImportFragment.class, null)
                     .commit();
         }
     }
diff --git a/app/src/main/java/it/reyboz/bustorino/backend/mato/MQTTMatoClient.kt b/app/src/main/java/it/reyboz/bustorino/backend/mato/MQTTMatoClient.kt
--- a/app/src/main/java/it/reyboz/bustorino/backend/mato/MQTTMatoClient.kt
+++ b/app/src/main/java/it/reyboz/bustorino/backend/mato/MQTTMatoClient.kt
@@ -24,7 +24,7 @@
     private var isStarted = false
     private var subscribedToAll = false
 
-    private lateinit var client: MqttAndroidClient
+    private var client: MqttAndroidClient? = null
     //private var clientID = ""
 
     private val respondersMap = HashMap<String, ArrayList<WeakReference<MQTTMatoListener>>>()
@@ -66,9 +66,9 @@
 
         Log.d(DEBUG_TAG,"client name: $clientID")
         //actually connect
-        client.connect(options,null, iMqttActionListener)
+        client!!.connect(options,null, iMqttActionListener)
         isStarted = true
-        client.setCallback(this)
+        client!!.setCallback(this)
 
         if (this.context ==null)
             this.context = context.applicationContext
@@ -92,8 +92,8 @@
                 disconnectedBufferOptions.bufferSize = 100
                 disconnectedBufferOptions.isPersistBuffer = false
                 disconnectedBufferOptions.isDeleteOldestMessages = false
-                client.setBufferOpts(disconnectedBufferOptions)
-                client.subscribe(topic, QoS.AtMostOnce.value)
+                client!!.setBufferOpts(disconnectedBufferOptions)
+                client!!.subscribe(topic, QoS.AtMostOnce.value)
                 isStarted = true
             }
 
@@ -122,7 +122,7 @@
                 connectTopic(topic)
                 //wait for connection
             } else {
-                client.subscribe(topic, QoS.AtMostOnce.value)
+                client!!.subscribe(topic, QoS.AtMostOnce.value)
             }
         }
 
@@ -156,7 +156,7 @@
             //if (done) break
             if (v.isEmpty()){
                 //actually unsubscribe
-                client.unsubscribe( mapTopic(line))
+                client!!.unsubscribe( mapTopic(line))
             }
             removed = done || removed
         }
@@ -227,7 +227,7 @@
                             if(elms.isEmpty())
                                 respondersMap.remove(line)
                             else {
-                                client.subscribe(topic, QoS.AtMostOnce.value, null, null)
+                                client!!.subscribe(topic, QoS.AtMostOnce.value, null, null)
                                 Log.d(DEBUG_TAG, "Resubscribed with topic $topic")
                             }
                         }
@@ -327,7 +327,7 @@
                 //try unsubscribing to all
                 if(emptyResp) {
                     Log.d(DEBUG_TAG, "Unsubscribe all")
-                    client.unsubscribe(LINES_ALL)
+                    client!!.unsubscribe(LINES_ALL)
                 }
             }
             //Log.d(DEBUG_TAG, "We have update on line $lineId, vehicle $vehicleId")
@@ -353,7 +353,7 @@
     }*/
 
     fun disconnect(){
-        client.disconnect()
+        client?.disconnect()
     }
 
 
diff --git a/app/src/main/java/it/reyboz/bustorino/data/PreferencesHolder.java b/app/src/main/java/it/reyboz/bustorino/data/PreferencesHolder.java
--- a/app/src/main/java/it/reyboz/bustorino/data/PreferencesHolder.java
+++ b/app/src/main/java/it/reyboz/bustorino/data/PreferencesHolder.java
@@ -39,6 +39,7 @@
     public static final String DB_LAST_UPDATE_KEY = "NextGenDB.LastDBUpdate";
     public static final String PREF_FAVORITE_LINES = "pref_favorite_lines";
 
+    public static final Set<String> KEYS_MERGE_SET = Set.of(PREF_FAVORITE_LINES);
     public static final Set<String> IGNORE_KEYS_LOAD_MAIN = Set.of(PREF_GTFS_DB_VERSION, PREF_INTRO_ACTIVITY_RUN, DB_GTT_VERSION_KEY, DB_LAST_UPDATE_KEY);
 
     public static SharedPreferences getMainSharedPreferences(Context context){
diff --git a/app/src/main/java/it/reyboz/bustorino/fragments/TestSavingFragment.kt b/app/src/main/java/it/reyboz/bustorino/fragments/BackupImportFragment.kt
rename from app/src/main/java/it/reyboz/bustorino/fragments/TestSavingFragment.kt
rename to app/src/main/java/it/reyboz/bustorino/fragments/BackupImportFragment.kt
--- a/app/src/main/java/it/reyboz/bustorino/fragments/TestSavingFragment.kt
+++ b/app/src/main/java/it/reyboz/bustorino/fragments/BackupImportFragment.kt
@@ -18,7 +18,7 @@
 import it.reyboz.bustorino.R
 import it.reyboz.bustorino.data.PreferencesHolder
 import it.reyboz.bustorino.data.UserDB
-import it.reyboz.bustorino.util.Saving
+import it.reyboz.bustorino.util.ImportExport
 import java.io.*
 import java.text.DateFormat
 import java.text.SimpleDateFormat
@@ -30,10 +30,10 @@
 
 /**
  * A simple [Fragment] subclass.
- * Use the [TestSavingFragment.newInstance] factory method to
+ * Use the [BackupImportFragment.newInstance] factory method to
  * create an instance of this fragment.
  */
-class TestSavingFragment : Fragment() {
+class BackupImportFragment : Fragment() {
 
     private val saveFileLauncher =
         registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
@@ -162,13 +162,13 @@
             //write main preferences
             zipOutputStream.putNextEntry(ZipEntry(MAIN_PREF_NAME))
             var sharedPrefs = PreferencesHolder.getMainSharedPreferences(context)
-            var jsonPref = Saving.writeSharedPreferencesIntoJSON(sharedPrefs)
+            var jsonPref = ImportExport.writeSharedPreferencesIntoJSON(sharedPrefs)
             writeStringToZipOS(jsonPref.toString(2), zipOutputStream)
             zipOutputStream.closeEntry()
 
             zipOutputStream.putNextEntry(ZipEntry(APP_PREF_NAME))
             sharedPrefs = PreferencesHolder.getAppPreferences(context)
-            jsonPref = Saving.writeSharedPreferencesIntoJSON(sharedPrefs)
+            jsonPref = ImportExport.writeSharedPreferencesIntoJSON(sharedPrefs)
             writeStringToZipOS(jsonPref.toString(2), zipOutputStream)
             zipOutputStream.closeEntry()
             //add CSV
@@ -210,7 +210,7 @@
                             val jsonString = readFileToString(zipstream)
                             try {
                                 val pref = PreferencesHolder.getAppPreferences(context)
-                                Saving.importJsonToSharedPreferences(pref, jsonString, null, Regex("osmdroid\\."))
+                                ImportExport.importJsonToSharedPreferences(pref, jsonString, null, Regex("osmdroid\\."))
                             } catch (e: Exception){
                                 Log.e(DEBUG_TAG, "Cannot read app preferences from file")
                                 e.printStackTrace()
@@ -223,7 +223,8 @@
                                 val pref = PreferencesHolder.getMainSharedPreferences(context)
                                 //In the future, if we move the favorite lines to a different file,
                                 // We should check here if the key is in the jsonObject, and copy it to the other file
-                                Saving.importJsonToSharedPreferences(pref, jsonString, PreferencesHolder.IGNORE_KEYS_LOAD_MAIN, null)
+                                ImportExport.importJsonToSharedPreferences(pref, jsonString, PreferencesHolder.IGNORE_KEYS_LOAD_MAIN, null,
+                                    PreferencesHolder.KEYS_MERGE_SET)
                             } catch (e: Exception){
                                 Log.e(DEBUG_TAG, "Cannot read main preferences from file")
                                 e.printStackTrace()
@@ -279,7 +280,7 @@
 
         @JvmStatic
         fun newInstance() =
-            TestSavingFragment().apply {
+            BackupImportFragment().apply {
                 arguments = Bundle() /*.apply {
                     putString(ARG_PARAM1, param1)
                     putString(ARG_PARAM2, param2)
diff --git a/app/src/main/java/it/reyboz/bustorino/fragments/SettingsFragment.java b/app/src/main/java/it/reyboz/bustorino/fragments/SettingsFragment.java
--- a/app/src/main/java/it/reyboz/bustorino/fragments/SettingsFragment.java
+++ b/app/src/main/java/it/reyboz/bustorino/fragments/SettingsFragment.java
@@ -18,6 +18,7 @@
 package it.reyboz.bustorino.fragments;
 
 import android.content.Context;
+import android.content.Intent;
 import android.content.SharedPreferences;
 import android.os.Bundle;
 import android.os.Handler;
@@ -33,6 +34,7 @@
 import androidx.work.OneTimeWorkRequest;
 import androidx.work.WorkInfo;
 import androidx.work.WorkManager;
+import it.reyboz.bustorino.ActivityBackup;
 import it.reyboz.bustorino.R;
 import it.reyboz.bustorino.data.DatabaseUpdate;
 import it.reyboz.bustorino.data.GtfsMaintenanceWorker;
@@ -89,15 +91,24 @@
         Preference dbUpdateNow = findPreference("pref_db_update_now");
         if (dbUpdateNow!=null)
         dbUpdateNow.setOnPreferenceClickListener(
-                new Preference.OnPreferenceClickListener() {
-                    @Override
-                    public boolean onPreferenceClick(@NonNull Preference preference) {
-                        //trigger update
-                        if(getContext()!=null) {
-                            DatabaseUpdate.requestDBUpdateWithWork(getContext().getApplicationContext(), true, true);
-                            Toast.makeText(getContext(),R.string.requesting_db_update,Toast.LENGTH_SHORT).show();
-                            return true;
-                        }
+                preference -> {
+                    //trigger update
+                    if(getContext()!=null) {
+                        DatabaseUpdate.requestDBUpdateWithWork(getContext().getApplicationContext(), true, true);
+                        Toast.makeText(getContext(),R.string.requesting_db_update,Toast.LENGTH_SHORT).show();
+                        return true;
+                    }
+                    return false;
+                }
+        );
+        //set click listener on backup item
+        final Preference backupPref = findPreference("pref_backup_open");
+        if (backupPref!=null) backupPref.setOnPreferenceClickListener(
+                preference -> {
+                    if(getActivity()!=null){
+                        startActivity( new Intent(getActivity().getApplicationContext(), ActivityBackup.class) );
+                        return true;
+                    } else {
                         return false;
                     }
                 }
diff --git a/app/src/main/java/it/reyboz/bustorino/util/Saving.kt b/app/src/main/java/it/reyboz/bustorino/util/ImportExport.kt
rename from app/src/main/java/it/reyboz/bustorino/util/Saving.kt
rename to app/src/main/java/it/reyboz/bustorino/util/ImportExport.kt
--- a/app/src/main/java/it/reyboz/bustorino/util/Saving.kt
+++ b/app/src/main/java/it/reyboz/bustorino/util/ImportExport.kt
@@ -8,7 +8,7 @@
 import java.io.*
 
 
-class Saving {
+class ImportExport {
 
     companion object{
 
@@ -87,10 +87,20 @@
             }
             return editor.commit()
         }
-
+        fun importJsonToSharedPreferences(sharedPreferences: SharedPreferences,
+                                          allJsonAsString: String,
+                                          ignoreKeys: Set<String>?,
+                                          ignoreKeyRegex: Regex?): Int{
+            return importJsonToSharedPreferences(sharedPreferences, allJsonAsString,
+                ignoreKeys, ignoreKeyRegex, HashSet())
+        }
 
         fun importJsonToSharedPreferences(sharedPreferences: SharedPreferences,
-                                          allJsonAsString: String, ignoreKeys: Set<String>?, ignoreKeyRegex: Regex?): Int {
+                                          allJsonAsString: String,
+                                          ignoreKeys: Set<String>?,
+                                          ignoreKeyRegex: Regex?,
+                                          mergeSetKeys: Set<String>
+                                          ): Int {
             // Parse JSON
             val jsonObject = JSONObject(allJsonAsString)
 
@@ -111,6 +121,8 @@
                         is String -> editor.putString(key, value)
                         is JSONArray -> { // Handle arrays
                             val set = mutableSetOf<String>()
+                            if (mergeSetKeys.contains(key))
+                                sharedPreferences.getStringSet(key, mutableSetOf())?.let { set.addAll(it) }
                             for (i in 0 until value.length()) {
                                 set.add(value.optString(i))
                             }
diff --git a/app/src/main/res/layout/activity_experiments.xml b/app/src/main/res/layout/activity_container_fragment.xml
rename from app/src/main/res/layout/activity_experiments.xml
rename to app/src/main/res/layout/activity_container_fragment.xml
diff --git a/app/src/main/res/layout/fragment_test_saving.xml b/app/src/main/res/layout/fragment_test_saving.xml
--- a/app/src/main/res/layout/fragment_test_saving.xml
+++ b/app/src/main/res/layout/fragment_test_saving.xml
@@ -3,7 +3,7 @@
              xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
-             tools:context=".fragments.TestSavingFragment">
+             tools:context=".fragments.BackupImportFragment">
     <androidx.constraintlayout.widget.ConstraintLayout
             android:layout_width="match_parent"
             android:layout_height="match_parent">
diff --git a/app/src/main/res/values-it/strings.xml b/app/src/main/res/values-it/strings.xml
--- a/app/src/main/res/values-it/strings.xml
+++ b/app/src/main/res/values-it/strings.xml
@@ -275,6 +275,9 @@
     <string name="grant_notification_permission">Abilita notifiche</string>
     <string name="notification_permission_granted">Notifiche abilitate</string>
 
+    <!-- BACKUP -->
+    <string name="backup_restore">Backup e ripristino</string>
+    <string name="backup_activity">Importa / esporta dati</string>
     <string name="saved_data">Dati salvati</string>
     <string name="btn_backup_message">Salva backup</string>
     <string name="btn_load_backup_message">Importa i dati dal backup</string>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -304,7 +304,9 @@
     <string name="close_tutorial_short">Close the tutorial</string>
     <string name="grant_notification_permission">Enable notifications</string>
     <string name="notification_permission_granted">Notifications enabled</string>
-
+    <!-- BACKUP -->
+    <string name="backup_restore">Backup and restore</string>
+    <string name="backup_activity">Import/export preferences</string>
     <string name="saved_data">Data saved</string>
     <string name="btn_backup_message">Backup to file</string>
     <string name="btn_load_backup_message">Import data from backup</string>
diff --git a/app/src/main/res/xml/preferences.xml b/app/src/main/res/xml/preferences.xml
--- a/app/src/main/res/xml/preferences.xml
+++ b/app/src/main/res/xml/preferences.xml
@@ -100,6 +100,13 @@
             />
     </androidx.preference.PreferenceCategory>
 
+    <androidx.preference.PreferenceCategory android:title="@string/backup_restore">
+        <androidx.preference.Preference
+            android:title="@string/backup_activity"
+            android:key="pref_backup_open"
+            />
+    </androidx.preference.PreferenceCategory>
+
     <androidx.preference.PreferenceCategory
             android:title="@string/settings_experimental">
         <androidx.preference.SwitchPreferenceCompat