diff --git a/res/values-it/strings.xml b/res/values-it/strings.xml
--- a/res/values-it/strings.xml
+++ b/res/values-it/strings.xml
@@ -184,6 +184,8 @@
     </string-array>
     <string name="pref_lines_click_msg">Mostra arrivi quando tocchi una fermata</string>
     <string name="pref_experimental_msg">Abilita esperimenti</string>
+    <string name="pref_shown_startup">Schermata da mostrare all\'avvio</string>
+    <string name="pref_shown_startup_def_desc">Tocca per cambiare</string>
 
 
 
diff --git a/res/values/keys.xml b/res/values/keys.xml
--- a/res/values/keys.xml
+++ b/res/values/keys.xml
@@ -3,4 +3,11 @@
            tools:ignore="MissingTranslation">
     <string name="pref_layout">layout_pref</string>
     <string name="pref_update_db_now">pref_update_db_now</string>
+    
+    <array name="first_screen_values">
+        <item>arrivals</item>
+        <item>favorites</item>
+        <item>map</item>
+        <item>lines</item>
+    </array>
 </resources>
\ No newline at end of file
diff --git a/res/values/strings.xml b/res/values/strings.xml
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -201,10 +201,19 @@
         <item>CAPITALIZE_FIRST</item>
 
     </array>
+    <string name="pref_shown_startup">Section to show on startup</string>
+    <string name="pref_shown_startup_def_desc">Touch to change it</string>
     <string name="pref_lines_click_msg">Show arrivals touching on stop</string>
     <string name="pref_experimental_msg">Enable experiments</string>
     
     <!-- lines -->
     <string name="long_press_stop_4_options">Long press the stop for options</string>
 
+    <array name="first_screen_shown">
+        <item>@string/nav_arrivals_text</item>
+        <item>@string/nav_favorites_text</item>
+        <item>@string/nav_map_text</item>
+        <item>@string/lines</item>
+    </array>
+
 </resources>
diff --git a/res/xml/preferences.xml b/res/xml/preferences.xml
--- a/res/xml/preferences.xml
+++ b/res/xml/preferences.xml
@@ -2,6 +2,16 @@
 <androidx.preference.PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto">
 
+    <androidx.preference.PreferenceCategory android:title="@string/general_settings">
+        <androidx.preference.ListPreference
+            android:key="startup_screen_to_show"
+            android:entries="@array/first_screen_shown"
+            android:entryValues="@array/first_screen_values"
+            android:title="@string/pref_shown_startup"
+            android:summary="%s"
+            />
+    </androidx.preference.PreferenceCategory>
+
     <androidx.preference.PreferenceCategory
             android:title="@string/pref_recents_group_title">
         <!--
diff --git a/src/it/reyboz/bustorino/ActivityPrincipal.java b/src/it/reyboz/bustorino/ActivityPrincipal.java
--- a/src/it/reyboz/bustorino/ActivityPrincipal.java
+++ b/src/it/reyboz/bustorino/ActivityPrincipal.java
@@ -77,6 +77,7 @@
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_principal);
         final SharedPreferences theShPr = getMainSharedPreferences();
+        boolean showingArrivalsForStop = false;
 
         //database check
         GtfsDatabase gtfsDB = GtfsDatabase.Companion.getGtfsDatabase(this);
@@ -189,10 +190,12 @@
             //setBusStopSearchByIDEditText(busStopID);
 
             requestArrivalsForStopID(busStopID);
+            showingArrivalsForStop = true;
         }
         //Try (hopefully) database update
         if(!dataUpdateRequested)
             DatabaseUpdate.requestDBUpdateWithWork(this, false, false);
+
         /*
         Watch for database update
          */
@@ -224,7 +227,21 @@
 
                 });
         // show the main fragment
-        showMainFragment();
+        String vl = PreferenceManager.getDefaultSharedPreferences(this).getString(SettingsFragment.PREF_KEY_STARTUP_SCREEN, "");
+        //if (vl.length() == 0 || vl.equals("arrivals")) {
+        //    showMainFragment();
+        Log.d(DEBUG_TAG, "The default screen to open is: "+vl);
+        if(showingArrivalsForStop){
+            showMainFragment(false);
+        } else if (vl.equals("map")){
+            requestMapFragment(false);
+        } else if(vl.equals("favorites")){
+            checkAndShowFavoritesFragment(getSupportFragmentManager(), false);
+        } else if(vl.equals("lines")){
+            showLinesFragment(getSupportFragmentManager(), false, null);
+        } else{
+            showMainFragment(false);
+        }
 
 
     }
@@ -250,50 +267,19 @@
                     } else if(menuItem.getItemId() == R.id.nav_favorites_item){
                         closeDrawerIfOpen();
                         //get Fragment
-                        FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
-                        FavoritesFragment fragment = FavoritesFragment.newInstance();
-                        ft.replace(R.id.mainActContentFrame,fragment, TAG_FAVORITES)
-                            .addToBackStack("main");
-                        ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
-                        ft.commit();
+                        checkAndShowFavoritesFragment(getSupportFragmentManager(), true);
                         return true;
                     } else if(menuItem.getItemId() == R.id.nav_arrivals){
                         closeDrawerIfOpen();
-                        showMainFragment();
+                        showMainFragment(true);
                         return true;
                     } else if(menuItem.getItemId() == R.id.nav_map_item){
                         closeDrawerIfOpen();
-                        final String permission = Manifest.permission.WRITE_EXTERNAL_STORAGE;
-                        int result = askForPermissionIfNeeded(permission, STORAGE_PERMISSION_REQ);
-                        switch (result) {
-                            case PERMISSION_OK:
-                                createAndShowMapFragment(null);
-                                break;
-                            case PERMISSION_ASKING:
-                                permissionDoneRunnables.put(permission,
-                                        () -> createAndShowMapFragment(null));
-                                break;
-                            case PERMISSION_NEG_CANNOT_ASK:
-                                String storage_perm = getString(R.string.storage_permission);
-                                String text = getString(R.string.too_many_permission_asks,  storage_perm);
-                                Toast.makeText(getApplicationContext(),text, Toast.LENGTH_LONG).show();
-                        }
+                        requestMapFragment(true);
                         return true;
                     } else if (menuItem.getItemId() == R.id.nav_lines_item) {
                         closeDrawerIfOpen();
-                        FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
-                        Fragment f = getSupportFragmentManager().findFragmentByTag(LinesFragment.FRAGMENT_TAG);
-                        if(f!=null){
-                            ft.replace(R.id.mainActContentFrame, f, LinesFragment.FRAGMENT_TAG);
-                        }else{
-                            //use new method
-                            ft.replace(R.id.mainActContentFrame,LinesFragment.class,null,LinesFragment.FRAGMENT_TAG);
-                        }
-
-                                ft.setReorderingAllowed(true)
-                                .addToBackStack("lines")
-                                .setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE)
-                                .commit();
+                        showLinesFragment(getSupportFragmentManager(), true,null);
                         return true;
                     }
                     //selectDrawerItem(menuItem);
@@ -438,8 +424,8 @@
      * @param fraMan the fragmentManager
      * @param fragment the fragment
      */
-    private static void showMainFragment(FragmentManager fraMan, MainScreenFragment fragment){
-        fraMan.beginTransaction().replace(R.id.mainActContentFrame, fragment)
+    private static void showMainFragment(FragmentManager fraMan, MainScreenFragment fragment, boolean addToBackStack){
+        FragmentTransaction ft  = fraMan.beginTransaction().replace(R.id.mainActContentFrame, fragment)
                 .setReorderingAllowed(true)
                 .addToBackStack(null)
                 /*.setCustomAnimations(
@@ -448,11 +434,62 @@
                         R.anim.fade_in,   // popEnter
                         R.anim.slide_out  // popExit
                 )*/
+                .setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
+        if (addToBackStack)  ft.addToBackStack("MAIN_SCREEN");
+        ft.commit();
+    }
+
+    private void requestMapFragment(final boolean allowReturn){
+        final String permission = Manifest.permission.WRITE_EXTERNAL_STORAGE;
+        int result = askForPermissionIfNeeded(permission, STORAGE_PERMISSION_REQ);
+        switch (result) {
+            case PERMISSION_OK:
+                createAndShowMapFragment(null, allowReturn);
+                break;
+            case PERMISSION_ASKING:
+                permissionDoneRunnables.put(permission,
+                        () -> createAndShowMapFragment(null, allowReturn));
+                break;
+            case PERMISSION_NEG_CANNOT_ASK:
+                String storage_perm = getString(R.string.storage_permission);
+                String text = getString(R.string.too_many_permission_asks,  storage_perm);
+                Toast.makeText(getApplicationContext(),text, Toast.LENGTH_LONG).show();
+        }
+    }
+
+    private static void checkAndShowFavoritesFragment(FragmentManager fragmentManager,  boolean addToBackStack){
+        FragmentTransaction ft = fragmentManager.beginTransaction();
+        Fragment fragment = fragmentManager.findFragmentByTag(TAG_FAVORITES);
+        if(fragment!=null){
+            ft.replace(R.id.mainActContentFrame, fragment, TAG_FAVORITES);
+        }else{
+            //use new method
+            ft.replace(R.id.mainActContentFrame,FavoritesFragment.class,null,TAG_FAVORITES);
+        }
+        if (addToBackStack)
+            ft.addToBackStack("favorites_main");
+        ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE)
+                .setReorderingAllowed(true);
+        ft.commit();
+    }
+
+    private static void showLinesFragment(@NonNull FragmentManager fragmentManager,  boolean addToBackStack, @Nullable Bundle fragArgs){
+        FragmentTransaction ft = fragmentManager.beginTransaction();
+        Fragment f = fragmentManager.findFragmentByTag(LinesFragment.FRAGMENT_TAG);
+        if(f!=null){
+            ft.replace(R.id.mainActContentFrame, f, LinesFragment.FRAGMENT_TAG);
+        }else{
+            //use new method
+            ft.replace(R.id.mainActContentFrame,LinesFragment.class,fragArgs,LinesFragment.FRAGMENT_TAG);
+        }
+        if (addToBackStack)
+            ft.addToBackStack("lines");
+        ft.setReorderingAllowed(true)
                 .setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE)
                 .commit();
     }
 
-    private MainScreenFragment showMainFragment(){
+    private MainScreenFragment showMainFragment(boolean addToBackStack){
         FragmentManager fraMan = getSupportFragmentManager();
         Fragment fragment = fraMan.findFragmentByTag(MainScreenFragment.FRAGMENT_TAG);
         final MainScreenFragment mainScreenFragment;
@@ -463,7 +500,7 @@
 
 
             mainScreenFragment = (MainScreenFragment) fragment;
-            showMainFragment(fraMan, mainScreenFragment);
+            showMainFragment(fraMan, mainScreenFragment, addToBackStack);
             Log.d(DEBUG_TAG, "Found the main fragment");
         } else{
             mainScreenFragment = (MainScreenFragment) fragment;
@@ -554,7 +591,7 @@
                 probableFragment = (MainScreenFragment) fragment;
                 // set the flag
                 probableFragment.setSuppressArrivalsReload(true);
-                showMainFragment(fraMan, probableFragment);
+                showMainFragment(fraMan, probableFragment, true);
             } else {
                 // we have no fragment
                 probableFragment = createAndShowMainFragment();
@@ -582,16 +619,16 @@
 
     @Override
     public void showMapCenteredOnStop(Stop stop) {
-        createAndShowMapFragment(stop);
+        createAndShowMapFragment(stop, true);
     }
 
     //Map Fragment stuff
-    void createAndShowMapFragment(@Nullable Stop stop){
+    void createAndShowMapFragment(@Nullable Stop stop, boolean addToBackStack){
         FragmentManager fm = getSupportFragmentManager();
         FragmentTransaction ft = fm.beginTransaction();
         MapFragment fragment = stop == null? MapFragment.getInstance(): MapFragment.getInstance(stop);
         ft.replace(R.id.mainActContentFrame, fragment, MapFragment.FRAGMENT_TAG);
-        ft.addToBackStack(null);
+        if (addToBackStack) ft.addToBackStack(null);
         ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
         ft.commit();
     }
diff --git a/src/it/reyboz/bustorino/data/PreferencesHolder.java b/src/it/reyboz/bustorino/data/PreferencesHolder.java
--- a/src/it/reyboz/bustorino/data/PreferencesHolder.java
+++ b/src/it/reyboz/bustorino/data/PreferencesHolder.java
@@ -23,6 +23,8 @@
 
 import static android.content.Context.MODE_PRIVATE;
 
+import androidx.preference.PreferenceManager;
+
 /**
  * Static class for commonly used SharedPreference operations
  */
@@ -34,6 +36,10 @@
         return context.getSharedPreferences(context.getString(R.string.mainSharedPreferences), MODE_PRIVATE);
     }
 
+    public static SharedPreferences getAppPreferences(Context con){
+        return PreferenceManager.getDefaultSharedPreferences(con);
+    }
+
     public static int getGtfsDBVersion(SharedPreferences pref){
         return pref.getInt(PREF_GTFS_DB_VERSION,-1);
     }
diff --git a/src/it/reyboz/bustorino/fragments/LinesFragment.kt b/src/it/reyboz/bustorino/fragments/LinesFragment.kt
--- a/src/it/reyboz/bustorino/fragments/LinesFragment.kt
+++ b/src/it/reyboz/bustorino/fragments/LinesFragment.kt
@@ -19,6 +19,7 @@
 
 import android.content.Context
 import android.os.Bundle
+import android.os.Parcelable
 import android.util.Log
 import android.view.*
 import android.widget.*
@@ -42,7 +43,7 @@
 
     companion object {
         fun newInstance(){
-            val fragment = LinesFragment()
+            LinesFragment()
         }
         const val DEBUG_TAG="BusTO-LinesFragment"
         const val FRAGMENT_TAG="LinesFragment"
@@ -71,7 +72,9 @@
     private val linesComparator = Comparator<GtfsRoute> { a,b ->
         return@Comparator linesNameSorter.compare(a.shortName, b.shortName)
     }
-    private var firstClick = true;
+    private var firstClick = true
+    private var recyclerViewState:Parcelable? = null
+    private var patternsSpinnerState:Parcelable? = null
 
     private val adapterListener = object : StopAdapterListener {
         override fun onTappedStop(stop: Stop?) {
@@ -98,6 +101,10 @@
         }
     }
 
+    override fun onSaveInstanceState(outState: Bundle) {
+        super.onSaveInstanceState(outState)
+        Log.d(DEBUG_TAG, "saveInstanceState bundle: $outState")
+    }
 
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
                               savedInstanceState: Bundle?): View? {
@@ -115,14 +122,51 @@
         stopsRecyclerView.layoutManager = llManager
         //allow the context menu to be opened
         registerForContextMenu(stopsRecyclerView)
+        Log.d(DEBUG_TAG, "Called onCreateView for LinesFragment")
+        Log.d(DEBUG_TAG, "OnCreateView, selected line spinner pos: ${linesSpinner.selectedItemPosition}")
+        Log.d(DEBUG_TAG, "OnCreateView, selected patterns spinner pos: ${patternsSpinner.selectedItemPosition}")
+
+        //set requests
+        viewModel.routesGTTLiveData.observe(viewLifecycleOwner) {
+            setRoutes(it)
+        }
+
+        viewModel.patternsWithStopsByRouteLiveData.observe(viewLifecycleOwner){
+                patterns ->
+            run {
+                currentPatterns = patterns.sortedBy { p-> p.pattern.code }
+                //patterns. //sortedBy {-1*it.stopsIndices.size}// "${p.pattern.directionId} - ${p.pattern.headsign}" }
+                patternsAdapter?.let {
+                    it.clear()
+                    it.addAll(currentPatterns.map { p->"${p.pattern.directionId} - ${p.pattern.headsign}" })
+                    it.notifyDataSetChanged()
+                }
+
+                val  pos = patternsSpinner.selectedItemPosition
+                //might be possible that the selectedItem is different (larger than list size)
+                if(pos!= INVALID_POSITION && pos >= 0 && (pos < currentPatterns.size)){
+                    val p = currentPatterns[pos]
+                    Log.d(DEBUG_TAG, "Setting patterns with pos $pos and p gtfsID ${p.pattern.code}")
+                    setPatternAndReqStops(currentPatterns[pos])
+                }
+
+            }
+        }
+
+        viewModel.stopsForPatternLiveData.observe(viewLifecycleOwner){stops->
+            Log.d("BusTO-LinesFragment", "Setting stops from DB")
+            setCurrentStops(stops)
+        }
 
         if(context!=null) {
-            patternsAdapter = ArrayAdapter(context!!, android.R.layout.simple_spinner_dropdown_item, ArrayList<String>())
+            patternsAdapter = ArrayAdapter(requireContext(), android.R.layout.simple_spinner_dropdown_item, ArrayList<String>())
             patternsSpinner.adapter = patternsAdapter
-            linesAdapter = ArrayAdapter(context!!, android.R.layout.simple_spinner_dropdown_item, ArrayList<String>())
+            linesAdapter = ArrayAdapter(requireContext(), android.R.layout.simple_spinner_dropdown_item, ArrayList<String>())
             linesSpinner.adapter = linesAdapter
 
-
+            if (linesSpinner.onItemSelectedListener != null){
+                Log.d(DEBUG_TAG, "linesSpinner listener != null")
+            }
             linesSpinner.onItemSelectedListener = object: OnItemSelectedListener{
                 override fun onItemSelected(p0: AdapterView<*>?, p1: View?, pos: Int, p3: Long) {
                     val selRoute = currentRoutes.get(pos)
@@ -130,7 +174,7 @@
                     routeDescriptionTextView.text = selRoute.longName
                     val oldRoute = viewModel.getRouteIDQueried()
                     val resetSpinner = (oldRoute != null) && (oldRoute.trim() != selRoute.gtfsId.trim())
-                    Log.d(DEBUG_TAG, "Selected route: ${selRoute.gtfsId}, reset spinner: $resetSpinner")
+                    Log.d(DEBUG_TAG, "Selected route: ${selRoute.gtfsId}, reset spinner: $resetSpinner, oldRoute: $oldRoute")
                     //launch query for this gtfsID
                     viewModel.setRouteIDQuery(selRoute.gtfsId)
                     //reset spinner position
@@ -170,41 +214,16 @@
     override fun onResume() {
         super.onResume()
         mListener?.readyGUIfor(FragmentKind.LINES)
+
+        Log.d(DEBUG_TAG, "Resuming lines fragment")
+        //Log.d(DEBUG_TAG, "OnResume, selected line spinner pos: ${linesSpinner.selectedItemPosition}")
+        //Log.d(DEBUG_TAG, "OnResume, selected patterns spinner pos: ${patternsSpinner.selectedItemPosition}")
     }
 
-    override fun onActivityCreated(savedInstanceState: Bundle?) {
-        super.onActivityCreated(savedInstanceState)
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
         viewModel = ViewModelProvider(this).get(LinesViewModel::class.java)
-
-        //val lines = viewModel.();
-        viewModel.routesGTTLiveData.observe(this) {
-            setRoutes(it)
-        }
-
-        viewModel.patternsWithStopsByRouteLiveData.observe(this){
-            patterns ->
-            run {
-                currentPatterns = patterns.sortedBy { p-> p.pattern.code }
-                        //patterns. //sortedBy {-1*it.stopsIndices.size}// "${p.pattern.directionId} - ${p.pattern.headsign}" }
-                patternsAdapter?.let {
-                    it.clear()
-                    it.addAll(currentPatterns.map { p->"${p.pattern.directionId} - ${p.pattern.headsign}" })
-                    it.notifyDataSetChanged()
-                }
-
-                val  pos = patternsSpinner.selectedItemPosition
-                //might be possible that the selectedItem is different (larger than list size)
-                if(pos!= INVALID_POSITION && pos >= 0 && (pos < currentPatterns.size)){
-                    setPatternAndReqStops(currentPatterns[pos])
-                }
-
-            }
-        }
-
-        viewModel.stopsForPatternLiveData.observe(this){stops->
-            Log.d("BusTO-LinesFragment", "Setting stops from DB")
-            setCurrentStops(stops)
-        }
+        Log.d(DEBUG_TAG, "Fragment onCreate")
 
     }
 
@@ -213,11 +232,42 @@
     }
 
     private fun setRoutes(routes: List<GtfsRoute>){
+        Log.d(DEBUG_TAG, "Resetting routes")
         currentRoutes = routes.sortedWith<GtfsRoute>(linesComparator)
 
+        if (linesAdapter!=null){
+
+            var selGtfsRoute = viewModel.getRouteIDQueried()
+            var selPatternIndex = 0
+            if(selGtfsRoute == null){
+                selGtfsRoute =""
+            }
+            val adapter = linesAdapter!!
+
+            if (adapter.isEmpty) {
+                Log.d(DEBUG_TAG, "Lines adapter is empty")
+            }
+            else{
+                adapter.clear()
+
+            }
+            adapter.addAll(currentRoutes.map { r -> r.shortName })
+            adapter.notifyDataSetChanged()
+            for(j in 0 until currentRoutes.size){
+                val route = currentRoutes[j]
+                if (route.gtfsId == selGtfsRoute) {
+                    selPatternIndex = j
+                    Log.d(DEBUG_TAG, "Route $selGtfsRoute has index $j")
+                }
+            }
+            linesSpinner.setSelection(selPatternIndex)
+            //
+        }
+        /*
         linesAdapter?.clear()
         linesAdapter?.addAll(currentRoutes.map { r -> r.shortName })
         linesAdapter?.notifyDataSetChanged()
+         */
     }
 
     private fun setCurrentStops(stops: List<Stop>){
@@ -227,7 +277,7 @@
         val numStops = stopsSorted.size
         Log.d(DEBUG_TAG, "RecyclerView adapter is: ${stopsRecyclerView.adapter}")
 
-        var setNewAdapter = true;
+        var setNewAdapter = true
         if(stopsRecyclerView.adapter is StopRecyclerAdapter){
             val adapter = stopsRecyclerView.adapter as StopRecyclerAdapter
             if(adapter.stops.size == stopsSorted.size && (adapter.stops.get(0).gtfsID == stopsSorted.get(0).gtfsID)
@@ -268,10 +318,9 @@
         if (v.id == R.id.patternStopsRecyclerView) {
             // if we aren't attached to activity, return null
             if (activity == null) return
-            val inflater = activity!!.menuInflater
+            val inflater = requireActivity().menuInflater
             inflater.inflate(R.menu.menu_line_item, menu)
 
-
         }
     }
 
@@ -292,10 +341,52 @@
             mListener!!.showMapCenteredOnStop(stop)
             return true
         } else if (acId == R.id.action_show_arrivals){
-            mListener?.requestArrivalsForStopID(stop.ID);
+            mListener?.requestArrivalsForStopID(stop.ID)
             return true
         }
         return false
     }
 
+    override fun onStop() {
+        super.onStop()
+        Log.d(DEBUG_TAG, "Fragment stopped")
+
+        recyclerViewState = stopsRecyclerView.layoutManager?.onSaveInstanceState()
+        patternsSpinnerState = patternsSpinner.onSaveInstanceState()
+    }
+
+
+    override fun onStart() {
+        super.onStart()
+
+        Log.d(DEBUG_TAG, "OnStart, selected line spinner pos: ${linesSpinner.selectedItemPosition}")
+        Log.d(DEBUG_TAG, "OnStart, selected patterns spinner pos: ${patternsSpinner.selectedItemPosition}")
+
+        if (recyclerViewState!=null){
+            stopsRecyclerView.layoutManager?.onRestoreInstanceState(recyclerViewState)
+        }
+        if(patternsSpinnerState!=null){
+            patternsSpinner.onRestoreInstanceState(patternsSpinnerState)
+        }
+    }
+    /*
+    override fun onDestroyView() {
+        super.onDestroyView()
+        Log.d(DEBUG_TAG, "Fragment view destroyed")
+
+    }
+
+    override fun onDestroy() {
+        super.onDestroy()
+        Log.d(DEBUG_TAG, "Fragment destroyed")
+    }
+    */
+
+    override fun onViewStateRestored(savedInstanceState: Bundle?) {
+        super.onViewStateRestored(savedInstanceState)
+        Log.d(DEBUG_TAG, "OnViewStateRes, bundled saveinstancestate: $savedInstanceState")
+        Log.d(DEBUG_TAG, "OnViewStateRes, selected line spinner pos: ${linesSpinner.selectedItemPosition}")
+        Log.d(DEBUG_TAG, "OnViewStateRes, selected patterns spinner pos: ${patternsSpinner.selectedItemPosition}")
+    }
+
 }
\ No newline at end of file
diff --git a/src/it/reyboz/bustorino/fragments/LinesViewModel.kt b/src/it/reyboz/bustorino/fragments/LinesViewModel.kt
--- a/src/it/reyboz/bustorino/fragments/LinesViewModel.kt
+++ b/src/it/reyboz/bustorino/fragments/LinesViewModel.kt
@@ -19,6 +19,8 @@
     //val patternsByRouteLiveData: LiveData<List<MatoPattern>>
 
     private val routeIDToSearch = MutableLiveData<String>()
+    private var lastShownPatternStops = ArrayList<String>()
+
 
     val stopsForPatternLiveData = MutableLiveData<List<Stop>>()
     val executor = Executors.newFixedThreadPool(2)
@@ -38,9 +40,6 @@
         gtfsRepo.getPatternsWithStopsForRouteID(it)
 
     }
-    val routesName: LiveData<List<String>> = Transformations.map(routesGTTLiveData) {
-        it.map { route -> route.longName }
-    }
 
     fun setRouteIDQuery(routeID: String){
         routeIDToSearch.value = routeID
@@ -49,9 +48,13 @@
     fun getRouteIDQueried(): String?{
         return routeIDToSearch.value
     }
-    var shouldShowMessage = true;
+    var shouldShowMessage = true
 
-    fun requestStopsForGTFSIDs(gtfsIDs: List<String>){
+    private fun requestStopsForGTFSIDs(gtfsIDs: List<String>){
+        if (gtfsIDs.equals(lastShownPatternStops)){
+            //nothing to do
+            return
+        }
         oldRepo.requestStopsWithGtfsIDs(gtfsIDs) {
             if (it.isSuccess) {
                 stopsForPatternLiveData.postValue(it.result)
@@ -60,6 +63,9 @@
                 it.exception?.printStackTrace()
             }
         }
+        lastShownPatternStops.clear()
+        for(id in gtfsIDs)
+            lastShownPatternStops.add(id)
     }
 
     fun requestStopsForPatternWithStops(patternStops: MatoPatternWithStops){
diff --git a/src/it/reyboz/bustorino/fragments/SettingsFragment.java b/src/it/reyboz/bustorino/fragments/SettingsFragment.java
--- a/src/it/reyboz/bustorino/fragments/SettingsFragment.java
+++ b/src/it/reyboz/bustorino/fragments/SettingsFragment.java
@@ -42,6 +42,8 @@
             "androidx.preference.PreferenceFragment.DIALOG";
     //private static final
     Handler mHandler;
+    public final static String PREF_KEY_STARTUP_SCREEN="startup_screen_to_show";
+    private boolean setSummaryStartupPref = false;
 
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
@@ -64,7 +66,15 @@
         });
          */
 
-        //ListPreference preference = findPreference(R.string.arrival_times)
+        ListPreference startupScreenPref = findPreference(PREF_KEY_STARTUP_SCREEN);
+        if(startupScreenPref !=null){
+            if (startupScreenPref.getValue()==null){
+                startupScreenPref.setSummary(getString(R.string.nav_arrivals_text));
+                setSummaryStartupPref = true;
+            }
+        }
+
+        //Log.d("BusTO-PrefFrag","startup screen pref is "+startupScreenPref.getValue());
 
         Preference dbUpdateNow = findPreference("pref_db_update_now");
         if (dbUpdateNow!=null)
@@ -94,6 +104,10 @@
         Log.d(TAG,"Preference key "+key+" changed");
         //sometimes this happens
         if(getContext()==null) return;
+        if(key.equals(PREF_KEY_STARTUP_SCREEN) && setSummaryStartupPref && pref !=null){
+            ListPreference listPref = (ListPreference) pref;
+            pref.setSummary(listPref.getEntry());
+        }
         /*
         THIS CODE STAYS COMMENTED FOR FUTURE REFERENCES
         if (key.equals(getString(R.string.pref_key_num_recents))){
@@ -128,7 +142,7 @@
 
     private void convertStringPrefToIntIfNeeded(String preferenceKey, Context con){
         if (con == null) return;
-        SharedPreferences defaultSharedPref = PreferenceManager.getDefaultSharedPreferences(getContext());
+        SharedPreferences defaultSharedPref = PreferenceManager.getDefaultSharedPreferences(con);
         try{
 
             Integer val = defaultSharedPref.getInt(preferenceKey, 0);