diff --git a/app/build.gradle b/app/build.gradle
index c291f01..c8f1a64 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -1,8 +1,9 @@
 apply plugin: 'com.android.application'
 
 android {
+
     compileSdkVersion project.ext.compileSdkVersion
-    buildToolsVersion project.ext.buildToolsVersion
+    // buildToolsVersion is optional because the plugin uses a recommended version by default
 
     defaultConfig {
         applicationId project.ext.applicationId
@@ -14,26 +15,29 @@ android {
         vectorDrawables.useSupportLibrary = true
         resConfigs "en", "de", "id", "it", "ja", "nb-rNO", "nl"
     }
+
     buildTypes {
+
         release {
             minifyEnabled true
             shrinkResources true
             proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
         }
-        debug {
-//            minifyEnabled true
-//            shrinkResources true
-//            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
-        }
+
     }
 }
 
 dependencies {
+
     implementation fileTree(include: ['*.jar'], dir: 'libs')
-    implementation 'com.android.support:appcompat-v7:' + supportLibraryVersion
-    implementation 'com.android.support:design:' + supportLibraryVersion
-    implementation 'com.android.support:cardview-v7:' + supportLibraryVersion
-    implementation 'com.android.support.constraint:constraint-layout:' + constraintLayoutVersion
-    implementation 'org.osmdroid:osmdroid-android:' + osmdroidVersion
-    implementation 'com.google.code.gson:gson:' + gsonVersion
+
+    implementation "androidx.appcompat:appcompat:$appcompatVersion"
+    implementation "androidx.constraintlayout:constraintlayout:$constraintlayoutVersion"
+    implementation "androidx.cardview:cardview:$cardviewVersion"
+
+    implementation "com.google.android.material:material:$materialVersion"
+
+    implementation "org.osmdroid:osmdroid-android:$osmdroidVersion"
+    implementation "com.google.code.gson:gson:$gsonVersion"
+
 }
diff --git a/app/proguard-rules.pro b/app/proguard-rules.pro
index aea1a6a..fa3abe6 100644
--- a/app/proguard-rules.pro
+++ b/app/proguard-rules.pro
@@ -15,3 +15,7 @@
 #-keepclassmembers class fqcn.of.javascript.interface.for.webview {
 #   public *;
 #}
+
+# this was a test
+# https://github.com/y20k/trackbook/commit/a3457db5462d9b4ab50b3c38c5621eb992768b7c
+# -dontshrink
\ No newline at end of file
diff --git a/app/src/main/java/org/y20k/trackbook/MainActivity.java b/app/src/main/java/org/y20k/trackbook/MainActivity.java
index 675914c..e75c892 100755
--- a/app/src/main/java/org/y20k/trackbook/MainActivity.java
+++ b/app/src/main/java/org/y20k/trackbook/MainActivity.java
@@ -34,19 +34,6 @@ import android.os.Environment;
 import android.os.IBinder;
 import android.os.Vibrator;
 import android.preference.PreferenceManager;
-import android.support.annotation.NonNull;
-import android.support.annotation.Nullable;
-import android.support.design.widget.BottomNavigationView;
-import android.support.design.widget.FloatingActionButton;
-import android.support.design.widget.Snackbar;
-import android.support.v4.app.DialogFragment;
-import android.support.v4.app.Fragment;
-import android.support.v4.app.FragmentManager;
-import android.support.v4.app.FragmentStatePagerAdapter;
-import android.support.v4.content.ContextCompat;
-import android.support.v4.content.LocalBroadcastManager;
-import android.support.v7.app.AppCompatActivity;
-import android.support.v7.widget.CardView;
 import android.util.SparseArray;
 import android.view.MenuItem;
 import android.view.View;
@@ -54,6 +41,10 @@ import android.view.ViewGroup;
 import android.widget.Button;
 import android.widget.Toast;
 
+import com.google.android.material.bottomnavigation.BottomNavigationView;
+import com.google.android.material.floatingactionbutton.FloatingActionButton;
+import com.google.android.material.snackbar.Snackbar;
+
 import org.osmdroid.config.Configuration;
 import org.y20k.trackbook.helpers.DialogHelper;
 import org.y20k.trackbook.helpers.ExportHelper;
@@ -68,6 +59,17 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.cardview.widget.CardView;
+import androidx.core.content.ContextCompat;
+import androidx.fragment.app.DialogFragment;
+import androidx.fragment.app.Fragment;
+import androidx.fragment.app.FragmentManager;
+import androidx.fragment.app.FragmentStatePagerAdapter;
+import androidx.localbroadcastmanager.content.LocalBroadcastManager;
+
 
 /**
  * MainActivity class
@@ -264,9 +266,20 @@ public class MainActivity extends AppCompatActivity implements TrackbookKeys {
                 if (resultCode == Activity.RESULT_OK) {
                     // user chose CLEAR
                     handleStateAfterClear();
-                    LogHelper.v(LOG_TAG, "Save dialog result: CLEAR");
+                    LogHelper.v(LOG_TAG, "Clear map dialog result: CLEAR");
                 } else if (resultCode == Activity.RESULT_CANCELED){
-                    LogHelper.v(LOG_TAG, "Clear map: User chose CANCEL.");
+                    LogHelper.v(LOG_TAG, "Clear map dialog result: User chose CANCEL.");
+                }
+                break;
+            case RESULT_EMPTY_RECORDING_DIALOG:
+                if (resultCode == Activity.RESULT_OK) {
+                    // User chose RESUME RECORDING
+                    handleResumeButtonClick((View)mFloatingActionButtonMain);
+                    LogHelper.v(LOG_TAG, "Empty recording dialog result: RESUME");
+                } else if (resultCode == Activity.RESULT_CANCELED){
+                    // User chose CANCEL - do nothing just hide the sub menu
+                    showFloatingActionButtonMenu(false);
+                    LogHelper.v(LOG_TAG, "Empty recording dialog result: CANCEL");
                 }
                 break;
         }
@@ -339,9 +352,6 @@ public class MainActivity extends AppCompatActivity implements TrackbookKeys {
 
     /* Handles the visual state after a save action */
     private void handleStateAfterClear() {
-        // notify user
-        Toast.makeText(this, getString(R.string.toast_message_track_clear), Toast.LENGTH_LONG).show();
-
         // dismiss notification
         dismissNotification();
 
@@ -584,16 +594,24 @@ public class MainActivity extends AppCompatActivity implements TrackbookKeys {
 
         switch (mFloatingActionButtonState) {
             case FAB_STATE_DEFAULT:
+                mFloatingActionButtonMain.hide(); // workaround todo remove asap
                 mFloatingActionButtonMain.setImageResource(R.drawable.ic_fiber_manual_record_white_24dp);
+                if (mSelectedTab == FRAGMENT_ID_MAP) mFloatingActionButtonMain.show(); // workaround todo remove asap
                 break;
             case FAB_STATE_RECORDING:
+                mFloatingActionButtonMain.hide(); // workaround todo remove asap
                 mFloatingActionButtonMain.setImageResource(R.drawable.ic_fiber_manual_record_red_24dp);
+                if (mSelectedTab == FRAGMENT_ID_MAP) mFloatingActionButtonMain.show(); // workaround todo remove asap
                 break;
             case FAB_STATE_SAVE:
+                mFloatingActionButtonMain.hide(); // workaround todo remove asap
                 mFloatingActionButtonMain.setImageResource(R.drawable.ic_save_white_24dp);
+                if (mSelectedTab == FRAGMENT_ID_MAP) mFloatingActionButtonMain.show(); // workaround todo remove asap
                 break;
             default:
+                mFloatingActionButtonMain.hide(); // workaround todo remove asap
                 mFloatingActionButtonMain.setImageResource(R.drawable.ic_fiber_manual_record_white_24dp);
+                if (mSelectedTab == FRAGMENT_ID_MAP) mFloatingActionButtonMain.show(); // workaround todo remove asap
                 break;
         }
     }
@@ -602,20 +620,20 @@ public class MainActivity extends AppCompatActivity implements TrackbookKeys {
     /* Shows (and hides) the sub menu of the floating action button */
     private void showFloatingActionButtonMenu(boolean visible) {
         if (visible) {
-            mFloatingActionButtonSubResume.setVisibility(View.VISIBLE);
+            mFloatingActionButtonSubResume.show();
             mFloatingActionButtonSubResumeLabel.setVisibility(View.VISIBLE);
-            mFloatingActionButtonSubClear.setVisibility(View.VISIBLE);
+            mFloatingActionButtonSubClear.show();
             mFloatingActionButtonSubClearLabel.setVisibility(View.VISIBLE);
-            mFloatingActionButtonSubSave.setVisibility(View.VISIBLE);
+            mFloatingActionButtonSubSave.show();
             mFloatingActionButtonSubSaveLabel.setVisibility(View.VISIBLE);
             mFloatingActionButtonSubMenuVisible = true;
         } else {
-            mFloatingActionButtonSubResume.setVisibility(View.INVISIBLE);
+            mFloatingActionButtonSubResume.hide();
             mFloatingActionButtonSubResumeLabel.setVisibility(View.INVISIBLE);
-            mFloatingActionButtonSubClear.setVisibility(View.INVISIBLE);
+            mFloatingActionButtonSubClear.hide();
             mFloatingActionButtonSubClearLabel.setVisibility(View.INVISIBLE);
+            mFloatingActionButtonSubSave.hide();
             mFloatingActionButtonSubSaveLabel.setVisibility(View.INVISIBLE);
-            mFloatingActionButtonSubSave.setVisibility(View.INVISIBLE);
             mFloatingActionButtonSubMenuVisible = false;
         }
     }
diff --git a/app/src/main/java/org/y20k/trackbook/MainActivityMapFragment.java b/app/src/main/java/org/y20k/trackbook/MainActivityMapFragment.java
index f728141..5649b5f 100755
--- a/app/src/main/java/org/y20k/trackbook/MainActivityMapFragment.java
+++ b/app/src/main/java/org/y20k/trackbook/MainActivityMapFragment.java
@@ -31,15 +31,13 @@ import android.os.Bundle;
 import android.os.Handler;
 import android.os.SystemClock;
 import android.preference.PreferenceManager;
-import android.support.annotation.NonNull;
-import android.support.design.widget.Snackbar;
-import android.support.v4.app.Fragment;
-import android.support.v4.content.LocalBroadcastManager;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.Toast;
 
+import com.google.android.material.snackbar.Snackbar;
+
 import org.osmdroid.api.IMapController;
 import org.osmdroid.tileprovider.tilesource.TileSourceFactory;
 import org.osmdroid.util.GeoPoint;
@@ -48,6 +46,7 @@ import org.osmdroid.views.overlay.ItemizedIconOverlay;
 import org.osmdroid.views.overlay.compass.CompassOverlay;
 import org.osmdroid.views.overlay.compass.InternalCompassOrientationProvider;
 import org.y20k.trackbook.core.Track;
+import org.y20k.trackbook.helpers.DialogHelper;
 import org.y20k.trackbook.helpers.LocationHelper;
 import org.y20k.trackbook.helpers.LogHelper;
 import org.y20k.trackbook.helpers.MapHelper;
@@ -56,6 +55,12 @@ import org.y20k.trackbook.helpers.TrackbookKeys;
 
 import java.util.List;
 
+import androidx.annotation.NonNull;
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.fragment.app.DialogFragment;
+import androidx.fragment.app.Fragment;
+import androidx.localbroadcastmanager.content.LocalBroadcastManager;
+
 
 /**
  * MainActivityMapFragment class
@@ -124,7 +129,7 @@ public class MainActivityMapFragment extends Fragment implements TrackbookKeys {
         if (savedInstanceState != null) {
             Location savedLocation = savedInstanceState.getParcelable(INSTANCE_CURRENT_LOCATION);
             // check if saved location is still current
-            if (LocationHelper.isNewLocation(savedLocation)) {
+            if (LocationHelper.isCurrent(savedLocation)) {
                 mCurrentBestLocation = savedLocation;
             } else {
                 mCurrentBestLocation = null;
@@ -207,7 +212,7 @@ public class MainActivityMapFragment extends Fragment implements TrackbookKeys {
 
         // mark user's location on map
         if (mCurrentBestLocation != null && !mTrackerServiceRunning) {
-            mMyLocationOverlay = MapHelper.createMyLocationOverlay(mActivity, mCurrentBestLocation, LocationHelper.isNewLocation(mCurrentBestLocation));
+            mMyLocationOverlay = MapHelper.createMyLocationOverlay(mActivity, mCurrentBestLocation, LocationHelper.isCurrent(mCurrentBestLocation), false);
             mMapView.getOverlays().add(mMyLocationOverlay);
         }
 
@@ -307,18 +312,29 @@ public class MainActivityMapFragment extends Fragment implements TrackbookKeys {
         switch(requestCode) {
             case RESULT_SAVE_DIALOG:
                 if (resultCode == Activity.RESULT_OK) {
-                    // user chose SAVE - clear map AND save track
-                    clearMap(true);
-                    // FloatingActionButton state is already being handled in MainActivity
-                    ((MainActivity)mActivity).onFloatingActionButtonResult(requestCode, resultCode);
-                    LogHelper.v(LOG_TAG, "Save dialog result: SAVE");
+                    // user chose SAVE
+                    if (mTrack.getSize() > 0) {
+                        // Track is not empty - clear map AND save track
+                        clearMap(true);
+                        // FloatingActionButton state is already being handled in MainActivity
+                        ((MainActivity)mActivity).onFloatingActionButtonResult(requestCode, resultCode);
+                        LogHelper.v(LOG_TAG, "Save dialog result: SAVE");
+                    } else {
+                        // track is empty
+                        handleEmptyRecordingSaveRequest();
+                    }
                 } else if (resultCode == Activity.RESULT_CANCELED){
                     LogHelper.v(LOG_TAG, "Save dialog result: CANCEL");
                 }
                 break;
             case RESULT_CLEAR_DIALOG:
                 if (resultCode == Activity.RESULT_OK) {
-                    // User chose CLEAR - clear map, DO NOT save track
+                    // User chose CLEAR
+                    if (mTrack.getSize() > 0) {
+                        // Track is not empty - notify user
+                        Toast.makeText(mActivity, getString(R.string.toast_message_track_clear), Toast.LENGTH_LONG).show();
+                    }
+                    // clear map, DO NOT save track
                     clearMap(false);
                     // handle FloatingActionButton state in MainActivity
                     ((MainActivity)mActivity).onFloatingActionButtonResult(requestCode, resultCode);
@@ -326,6 +342,10 @@ public class MainActivityMapFragment extends Fragment implements TrackbookKeys {
                     LogHelper.v(LOG_TAG, "Clear dialog result: CANCEL");
                 }
                 break;
+            case RESULT_EMPTY_RECORDING_DIALOG:
+                // handle FloatingActionButton state and possible Resume-Action in MainActivity
+                ((MainActivity)mActivity).onFloatingActionButtonResult(requestCode, resultCode);
+                break;
         }
     }
 
@@ -444,6 +464,21 @@ public class MainActivityMapFragment extends Fragment implements TrackbookKeys {
     }
 
 
+    /* Handles case when user chose to save recording with zero waypoints */ // todo implement
+    private void handleEmptyRecordingSaveRequest() {
+        // prepare empty recording dialog ("Unable to save")
+        int dialogTitle = R.string.dialog_error_empty_recording_title;
+        String dialogMessage = getString(R.string.dialog_error_empty_recording_content);
+        int dialogPositiveButton = R.string.dialog_error_empty_recording_action_resume;
+        int dialogNegativeButton = R.string.dialog_default_action_cancel;
+        // show  empty recording dialog
+        DialogFragment dialogFragment = DialogHelper.newInstance(dialogTitle, dialogMessage, dialogPositiveButton, dialogNegativeButton);
+        dialogFragment.setTargetFragment(this, RESULT_EMPTY_RECORDING_DIALOG);
+        dialogFragment.show(((AppCompatActivity)mActivity).getSupportFragmentManager(), "EmptyRecordingDialog");
+        // results of dialog are handled by onActivityResult
+    }
+
+
     /* Start preliminary tracking for map */
     private void startPreliminaryTracking() {
         if (mLocationSystemSetting && !mLocalTrackerRunning) {
@@ -508,7 +543,7 @@ public class MainActivityMapFragment extends Fragment implements TrackbookKeys {
         mMapView.getOverlays().remove(mMyLocationOverlay);
         // only update while not tracking
         if (!mTrackerServiceRunning) {
-            mMyLocationOverlay = MapHelper.createMyLocationOverlay(mActivity, mCurrentBestLocation, LocationHelper.isNewLocation(mCurrentBestLocation));
+            mMyLocationOverlay = MapHelper.createMyLocationOverlay(mActivity, mCurrentBestLocation, LocationHelper.isCurrent(mCurrentBestLocation), false);
             mMapView.getOverlays().add(mMyLocationOverlay);
         }
     }
@@ -518,11 +553,16 @@ public class MainActivityMapFragment extends Fragment implements TrackbookKeys {
     private void drawTrackOverlay(Track track) {
         mMapView.getOverlays().remove(mTrackOverlay);
         mTrackOverlay = null;
-        if (track != null) {
+        if (track == null || track.getSize() == 0) {
+            LogHelper.i(LOG_TAG, "Waiting for a track. Showing preliminary location.");
+            mTrackOverlay = MapHelper.createMyLocationOverlay(mActivity, mCurrentBestLocation, false, mTrackerServiceRunning);
+            Toast.makeText(mActivity, mActivity.getString(R.string.toast_message_acquiring_location), Toast.LENGTH_LONG).show();
+        } else {
             LogHelper.v(LOG_TAG, "Drawing track overlay.");
             mTrackOverlay = MapHelper.createTrackOverlay(mActivity, track, mTrackerServiceRunning);
-            mMapView.getOverlays().add(mTrackOverlay);
         }
+        mMapView.getOverlays().add(mTrackOverlay);
+
     }
 
 
diff --git a/app/src/main/java/org/y20k/trackbook/MainActivityTrackFragment.java b/app/src/main/java/org/y20k/trackbook/MainActivityTrackFragment.java
index babed61..6d13f83 100755
--- a/app/src/main/java/org/y20k/trackbook/MainActivityTrackFragment.java
+++ b/app/src/main/java/org/y20k/trackbook/MainActivityTrackFragment.java
@@ -24,16 +24,6 @@ import android.content.IntentFilter;
 import android.location.Location;
 import android.os.AsyncTask;
 import android.os.Bundle;
-import android.support.annotation.NonNull;
-import android.support.annotation.Nullable;
-import android.support.constraint.ConstraintLayout;
-import android.support.constraint.Group;
-import android.support.design.widget.BottomSheetBehavior;
-import android.support.v4.app.DialogFragment;
-import android.support.v4.app.Fragment;
-import android.support.v4.app.FragmentActivity;
-import android.support.v4.content.ContextCompat;
-import android.support.v4.content.LocalBroadcastManager;
 import android.view.LayoutInflater;
 import android.view.MotionEvent;
 import android.view.View;
@@ -45,6 +35,8 @@ import android.widget.Spinner;
 import android.widget.TextView;
 import android.widget.Toast;
 
+import com.google.android.material.bottomsheet.BottomSheetBehavior;
+
 import org.osmdroid.api.IMapController;
 import org.osmdroid.tileprovider.tilesource.TileSourceFactory;
 import org.osmdroid.util.GeoPoint;
@@ -67,6 +59,16 @@ import java.io.File;
 import java.text.DateFormat;
 import java.util.Locale;
 
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.constraintlayout.widget.ConstraintLayout;
+import androidx.constraintlayout.widget.Group;
+import androidx.core.content.ContextCompat;
+import androidx.fragment.app.DialogFragment;
+import androidx.fragment.app.Fragment;
+import androidx.fragment.app.FragmentActivity;
+import androidx.localbroadcastmanager.content.LocalBroadcastManager;
+
 
 /**
  * MainActivityTrackFragment class
diff --git a/app/src/main/java/org/y20k/trackbook/Trackbook.java b/app/src/main/java/org/y20k/trackbook/Trackbook.java
index 5bfb1d2..34eed22 100755
--- a/app/src/main/java/org/y20k/trackbook/Trackbook.java
+++ b/app/src/main/java/org/y20k/trackbook/Trackbook.java
@@ -18,11 +18,12 @@ package org.y20k.trackbook;
 
 import android.app.Application;
 import android.os.Build;
-import android.support.v7.app.AppCompatDelegate;
 
 import org.y20k.trackbook.helpers.LogHelper;
 import org.y20k.trackbook.helpers.NightModeHelper;
 
+import androidx.appcompat.app.AppCompatDelegate;
+
 
 /**
  * Trackbook.class
diff --git a/app/src/main/java/org/y20k/trackbook/TrackerService.java b/app/src/main/java/org/y20k/trackbook/TrackerService.java
index 5e2ac62..1351397 100755
--- a/app/src/main/java/org/y20k/trackbook/TrackerService.java
+++ b/app/src/main/java/org/y20k/trackbook/TrackerService.java
@@ -37,8 +37,6 @@ import android.os.CountDownTimer;
 import android.os.Handler;
 import android.os.IBinder;
 import android.preference.PreferenceManager;
-import android.support.v4.app.NotificationCompat;
-import android.support.v4.content.LocalBroadcastManager;
 import android.widget.Toast;
 
 import org.y20k.trackbook.core.Track;
@@ -50,6 +48,9 @@ import org.y20k.trackbook.helpers.TrackbookKeys;
 
 import java.util.List;
 
+import androidx.core.app.NotificationCompat;
+import androidx.localbroadcastmanager.content.LocalBroadcastManager;
+
 import static android.hardware.Sensor.TYPE_STEP_COUNTER;
 
 
@@ -233,7 +234,7 @@ public class TrackerService extends Service implements TrackbookKeys, SensorEven
                 // load temp track file
                 mTrack = storageHelper.loadTrack(FILE_TEMP_TRACK);
                 // try to mark last waypoint as stopover
-                int lastWayPoint = mTrack.getWayPoints().size() - 1;
+                int lastWayPoint = mTrack.getSize() - 1;
                 if (lastWayPoint >= 0) {
                     mTrack.getWayPoints().get(lastWayPoint).setIsStopOver(true);
                 }
@@ -394,12 +395,17 @@ public class TrackerService extends Service implements TrackbookKeys, SensorEven
 
         boolean success = false;
         Location previousLocation = null;
-        int trackSize = mTrack.getWayPoints().size();
+        int trackSize = mTrack.getSize();
 
         if (trackSize == 0) {
-            // add first location to track
-            success = mTrack.addWayPoint(previousLocation, mCurrentBestLocation);
-
+            // if accurate AND current
+            if (LocationHelper.isAccurate(mCurrentBestLocation) && LocationHelper.isCurrent(mCurrentBestLocation)) {
+                // add first location to track
+                success = mTrack.addWayPoint(previousLocation, mCurrentBestLocation);
+            } else {
+                // just send a broadcast indicating that current location fix not not suited
+                broadcastTrackUpdate();
+            }
         } else {
             // get location of previous WayPoint
             previousLocation = mTrack.getWayPointLocation(trackSize - 1);
@@ -415,17 +421,20 @@ public class TrackerService extends Service implements TrackbookKeys, SensorEven
                 averageSpeed = distance / ((float) timeDifference / ONE_SECOND_IN_NANOSECOND);
             }
 
-            if (LocationHelper.isNewWayPoint(previousLocation, mCurrentBestLocation, averageSpeed)) {
-                // if new, add current best location to track
+            // if accurate AND new
+            if (LocationHelper.isAccurate(mCurrentBestLocation) && LocationHelper.isNewWayPoint(previousLocation, mCurrentBestLocation, averageSpeed)) {
+                // add current best location to track
                 success = mTrack.addWayPoint(previousLocation, mCurrentBestLocation);
             }
         }
 
         if (success) {
             if (mResumedFlag) {
-                // mark last location as stop over
-                int lastWayPoint = mTrack.getWayPoints().size() - 2;
-                mTrack.getWayPoints().get(lastWayPoint).setIsStopOver(true);
+                int lastWayPoint = mTrack.getSize() - 2;
+                if (lastWayPoint >= 0) {
+                    // mark last location as stop over
+                    mTrack.getWayPoints().get(lastWayPoint).setIsStopOver(true);
+                }
                 mResumedFlag = false;
             } else {
                 // update distance, if not resumed
diff --git a/app/src/main/java/org/y20k/trackbook/core/Track.java b/app/src/main/java/org/y20k/trackbook/core/Track.java
index 2f48aea..e2f7158 100755
--- a/app/src/main/java/org/y20k/trackbook/core/Track.java
+++ b/app/src/main/java/org/y20k/trackbook/core/Track.java
@@ -19,7 +19,6 @@ package org.y20k.trackbook.core;
 import android.location.Location;
 import android.os.Parcel;
 import android.os.Parcelable;
-import android.support.annotation.Nullable;
 
 import org.y20k.trackbook.helpers.LocationHelper;
 import org.y20k.trackbook.helpers.TrackbookKeys;
@@ -29,6 +28,8 @@ import java.util.Date;
 import java.util.GregorianCalendar;
 import java.util.List;
 
+import androidx.annotation.Nullable;
+
 
 /**
  * Track class
@@ -275,7 +276,12 @@ public class Track implements TrackbookKeys, Parcelable {
 
     /* Getter recorded distance */
     public Double getTrackDistance() {
-        return (double) mWayPoints.get(mWayPoints.size()-1).getDistanceToStartingPoint();
+        int size = mWayPoints.size();
+        if (size > 0) {
+            return (double)mWayPoints.get(size - 1).getDistanceToStartingPoint();
+        } else {
+            return (double)0f;
+        }
     }
 
 
diff --git a/app/src/main/java/org/y20k/trackbook/helpers/DialogHelper.java b/app/src/main/java/org/y20k/trackbook/helpers/DialogHelper.java
index cbdcb02..95f7955 100755
--- a/app/src/main/java/org/y20k/trackbook/helpers/DialogHelper.java
+++ b/app/src/main/java/org/y20k/trackbook/helpers/DialogHelper.java
@@ -21,8 +21,9 @@ import android.app.AlertDialog;
 import android.app.Dialog;
 import android.content.DialogInterface;
 import android.os.Bundle;
-import android.support.annotation.NonNull;
-import android.support.v4.app.DialogFragment;
+
+import androidx.annotation.NonNull;
+import androidx.fragment.app.DialogFragment;
 
 
 /**
diff --git a/app/src/main/java/org/y20k/trackbook/helpers/DropdownAdapter.java b/app/src/main/java/org/y20k/trackbook/helpers/DropdownAdapter.java
index 0fae97a..b3ee9c1 100755
--- a/app/src/main/java/org/y20k/trackbook/helpers/DropdownAdapter.java
+++ b/app/src/main/java/org/y20k/trackbook/helpers/DropdownAdapter.java
@@ -20,8 +20,6 @@ package org.y20k.trackbook.helpers;
 import android.app.Activity;
 import android.content.res.Resources;
 import android.database.DataSetObserver;
-import android.support.annotation.Nullable;
-import android.support.v7.widget.ThemedSpinnerAdapter;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
@@ -35,6 +33,9 @@ import java.io.File;
 import java.util.ArrayList;
 import java.util.List;
 
+import androidx.annotation.Nullable;
+import androidx.appcompat.widget.ThemedSpinnerAdapter;
+
 
 /**
  * DropdownHelper class
@@ -175,7 +176,9 @@ public class DropdownAdapter extends BaseAdapter implements ThemedSpinnerAdapter
         // fill list with track bundles
         mTrackBundleList = new ArrayList<>();
         for (File file : files) {
-            mTrackBundleList.add(new TrackBundle(file));
+            if (file.getName().endsWith(FILE_TYPE_TRACKBOOK_EXTENSION)) {
+                mTrackBundleList.add(new TrackBundle(file));
+            }
         }
 
     }
diff --git a/app/src/main/java/org/y20k/trackbook/helpers/ExportHelper.java b/app/src/main/java/org/y20k/trackbook/helpers/ExportHelper.java
index 8b1ab15..5816d16 100755
--- a/app/src/main/java/org/y20k/trackbook/helpers/ExportHelper.java
+++ b/app/src/main/java/org/y20k/trackbook/helpers/ExportHelper.java
@@ -20,7 +20,6 @@ import android.content.Context;
 import android.content.Intent;
 import android.location.Location;
 import android.os.Environment;
-import android.support.v4.content.FileProvider;
 import android.widget.Toast;
 
 import org.y20k.trackbook.R;
@@ -37,6 +36,8 @@ import java.util.Date;
 import java.util.Locale;
 import java.util.TimeZone;
 
+import androidx.core.content.FileProvider;
+
 /**
  * ExportHelper class
  */
diff --git a/app/src/main/java/org/y20k/trackbook/helpers/LocationHelper.java b/app/src/main/java/org/y20k/trackbook/helpers/LocationHelper.java
index 5f0041f..1b44300 100755
--- a/app/src/main/java/org/y20k/trackbook/helpers/LocationHelper.java
+++ b/app/src/main/java/org/y20k/trackbook/helpers/LocationHelper.java
@@ -22,12 +22,13 @@ import android.location.LocationListener;
 import android.location.LocationManager;
 import android.os.SystemClock;
 import android.provider.Settings;
-import android.support.annotation.Nullable;
 
 import java.util.List;
 import java.util.Locale;
 import java.util.concurrent.TimeUnit;
 
+import androidx.annotation.Nullable;
+
 
 /**
  * LocationHelper class
@@ -93,8 +94,8 @@ public final class LocationHelper implements TrackbookKeys {
 
         // check whether the new location fix is newer or older
         long timeDelta = location.getElapsedRealtimeNanos() - currentBestLocation.getElapsedRealtimeNanos();
-        boolean isSignificantlyNewer = timeDelta > TWO_MINUTES_IN_NANOSECONDS;
-        boolean isSignificantlyOlder = timeDelta < -TWO_MINUTES_IN_NANOSECONDS;
+        boolean isSignificantlyNewer = timeDelta > ONE_MINUTE_IN_NANOSECONDS;
+        boolean isSignificantlyOlder = timeDelta < -ONE_MINUTE_IN_NANOSECONDS;
         boolean isNewer = timeDelta > 0;
 
         // if it's been more than two minutes since the current location, use the new location because the user has likely moved
@@ -125,13 +126,19 @@ public final class LocationHelper implements TrackbookKeys {
     }
 
 
+    /* Checks accuracy of given location */
+    public static boolean isAccurate(Location location) {
+        return location.getAccuracy() < FIFTY_METER_RADIUS;
+    }
+
+
     /* Checks if given location is newer than two minutes */
-    public static boolean isNewLocation(Location location) {
+    public static boolean isCurrent(Location location) {
         if (location == null) {
             return false;
         } else {
             long locationAge = SystemClock.elapsedRealtimeNanos() - location.getElapsedRealtimeNanos();
-            return locationAge < TWO_MINUTES_IN_NANOSECONDS;
+            return locationAge < ONE_MINUTE_IN_NANOSECONDS;
         }
     }
 
diff --git a/app/src/main/java/org/y20k/trackbook/helpers/MapHelper.java b/app/src/main/java/org/y20k/trackbook/helpers/MapHelper.java
index f2d1b4c..e9759ee 100755
--- a/app/src/main/java/org/y20k/trackbook/helpers/MapHelper.java
+++ b/app/src/main/java/org/y20k/trackbook/helpers/MapHelper.java
@@ -19,7 +19,6 @@ package org.y20k.trackbook.helpers;
 import android.content.Context;
 import android.graphics.drawable.Drawable;
 import android.location.Location;
-import android.support.v4.content.ContextCompat;
 import android.widget.Toast;
 
 import org.osmdroid.util.GeoPoint;
@@ -34,6 +33,8 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
 
+import androidx.core.content.ContextCompat;
+
 /**
  * MapHelper class
  */
@@ -44,17 +45,20 @@ public final class MapHelper {
 
 
     /* Creates icon overlay for current position (used in MainActivity Fragment) */
-    public static ItemizedIconOverlay createMyLocationOverlay(final Context context, Location currentBestLocation, boolean locationIsNew) {
+    public static ItemizedIconOverlay createMyLocationOverlay(final Context context, Location currentBestLocation, boolean locationIsNew, boolean trackingActive) {
 
         final ArrayList<OverlayItem> overlayItems = new ArrayList<>();
 
         // create marker
         Drawable newMarker;
-        if (locationIsNew) {
+        if (locationIsNew && !trackingActive) {
             newMarker = ContextCompat.getDrawable(context, R.drawable.ic_my_location_dot_blue_24dp);
+        } else if (!locationIsNew && trackingActive) {
+            newMarker = ContextCompat.getDrawable(context, R.drawable.ic_my_location_dot_red_grey_24dp);
         } else {
-            newMarker = ContextCompat.getDrawable(context, R.drawable.ic_my_location_dot_grey_24dp);
+                newMarker = ContextCompat.getDrawable(context, R.drawable.ic_my_location_dot_blue_grey_24dp);
         }
+
         OverlayItem overlayItem = createOverlayItem(context, currentBestLocation);
         overlayItem.setMarker(newMarker);
 
@@ -83,13 +87,14 @@ public final class MapHelper {
     /* Creates icon overlay for track */
     public static ItemizedIconOverlay createTrackOverlay(final Context context, Track track, boolean trackingActive){
 
-        WayPoint wayPoint;
+        final ArrayList<OverlayItem> overlayItems = new ArrayList<>();
         boolean currentPosition;
         final int trackSize = track.getSize();
         final List<WayPoint> wayPoints = track.getWayPoints();
-        final ArrayList<OverlayItem> overlayItems = new ArrayList<>();
+        WayPoint wayPoint;
+
+        for (int i = 0; i < track.getSize(); i++) {
 
-        for (int i = 0 ; i < track.getSize() ; i++) {
             // get WayPoint and check if it is current position
             wayPoint = wayPoints.get(i);
             currentPosition = i == trackSize - 1;
@@ -112,7 +117,7 @@ public final class MapHelper {
             else if (trackingActive && currentPosition) {
                 if (wayPoint.getIsStopOver()) {
                     // stop over marker
-                    newMarker = ContextCompat.getDrawable(context, R.drawable.ic_my_location_dot_grey_24dp);
+                    newMarker = ContextCompat.getDrawable(context, R.drawable.ic_my_location_dot_blue_grey_24dp);
                 } else {
                     // default marker for this case
                     newMarker = ContextCompat.getDrawable(context, R.drawable.ic_my_location_dot_red_24dp);
diff --git a/app/src/main/java/org/y20k/trackbook/helpers/NightModeHelper.java b/app/src/main/java/org/y20k/trackbook/helpers/NightModeHelper.java
index fb5b754..2e1b9b8 100755
--- a/app/src/main/java/org/y20k/trackbook/helpers/NightModeHelper.java
+++ b/app/src/main/java/org/y20k/trackbook/helpers/NightModeHelper.java
@@ -22,9 +22,10 @@ import android.content.SharedPreferences;
 import android.content.res.Configuration;
 import android.os.Build;
 import android.preference.PreferenceManager;
-import android.support.v7.app.AppCompatDelegate;
 import android.view.View;
 
+import androidx.appcompat.app.AppCompatDelegate;
+
 
 /**
  * NightModeHelper class
diff --git a/app/src/main/java/org/y20k/trackbook/helpers/NotificationHelper.java b/app/src/main/java/org/y20k/trackbook/helpers/NotificationHelper.java
index de771a5..f3cc70d 100755
--- a/app/src/main/java/org/y20k/trackbook/helpers/NotificationHelper.java
+++ b/app/src/main/java/org/y20k/trackbook/helpers/NotificationHelper.java
@@ -26,15 +26,16 @@ import android.content.res.Resources;
 import android.graphics.Bitmap;
 import android.graphics.Canvas;
 import android.os.Build;
-import android.support.graphics.drawable.VectorDrawableCompat;
-import android.support.v4.app.NotificationCompat;
-import android.support.v4.app.TaskStackBuilder;
 
 import org.y20k.trackbook.MainActivity;
 import org.y20k.trackbook.R;
 import org.y20k.trackbook.TrackerService;
 import org.y20k.trackbook.core.Track;
 
+import androidx.core.app.NotificationCompat;
+import androidx.core.app.TaskStackBuilder;
+import androidx.vectordrawable.graphics.drawable.VectorDrawableCompat;
+
 
 /**
  * NotificationHelper class
diff --git a/app/src/main/java/org/y20k/trackbook/helpers/StorageHelper.java b/app/src/main/java/org/y20k/trackbook/helpers/StorageHelper.java
index 8b4e742..f063b86 100755
--- a/app/src/main/java/org/y20k/trackbook/helpers/StorageHelper.java
+++ b/app/src/main/java/org/y20k/trackbook/helpers/StorageHelper.java
@@ -18,8 +18,6 @@ package org.y20k.trackbook.helpers;
 
 import android.content.Context;
 import android.os.Environment;
-import android.support.annotation.Nullable;
-import android.support.v4.os.EnvironmentCompat;
 import android.widget.Toast;
 
 import com.google.gson.Gson;
@@ -42,6 +40,9 @@ import java.util.Comparator;
 import java.util.Date;
 import java.util.Locale;
 
+import androidx.annotation.Nullable;
+import androidx.core.os.EnvironmentCompat;
+
 
 /**
  * StorageHelper class
diff --git a/app/src/main/java/org/y20k/trackbook/helpers/TrackbookKeys.java b/app/src/main/java/org/y20k/trackbook/helpers/TrackbookKeys.java
index b474058..c1a5f59 100755
--- a/app/src/main/java/org/y20k/trackbook/helpers/TrackbookKeys.java
+++ b/app/src/main/java/org/y20k/trackbook/helpers/TrackbookKeys.java
@@ -75,23 +75,21 @@ public interface TrackbookKeys {
     int FRAGMENT_ID_MAP = 0;
     int FRAGMENT_ID_TRACKS = 1;
 
-    String FRAGMENT_TAG_MAP = "fragmentTagMap";
-    String FRAGMENT_TAG_TRACKS = "fragmentTagTracks";
-
-
     /* RESULTS */
     int RESULT_SAVE_DIALOG = 1;
     int RESULT_CLEAR_DIALOG = 2;
     int RESULT_DELETE_DIALOG = 3;
     int RESULT_EXPORT_DIALOG = 4;
+    int RESULT_EMPTY_RECORDING_DIALOG = 5;
 
     /* CONSTANTS */
     long ONE_SECOND_IN_NANOSECOND = 1000000000L;
     long EIGHT_HOURS_IN_MILLISECONDS = 43200000; // maximum tracking duration
     long FIFTEEN_SECONDS_IN_MILLISECONDS = 15000; // timer interval for tracking
     long FIVE_MINUTES_IN_NANOSECONDS = 5L * 60000000000L; // determines a stop over
-    long TWO_MINUTES_IN_NANOSECONDS = 2L * 60000000000L; // defines an old location
+    long ONE_MINUTE_IN_NANOSECONDS = 1L * 60000000000L; // defines an old location
     int MAXIMUM_TRACK_FILES = 25;
+    int FIFTY_METER_RADIUS = 50;
 
     /* FILE */
     String FILE_TYPE_GPX_EXTENSION = ".gpx";
diff --git a/app/src/main/java/org/y20k/trackbook/layout/DodgeAbleLayoutBehavior.java b/app/src/main/java/org/y20k/trackbook/layout/DodgeAbleLayoutBehavior.java
index 4befaac..e1969b8 100755
--- a/app/src/main/java/org/y20k/trackbook/layout/DodgeAbleLayoutBehavior.java
+++ b/app/src/main/java/org/y20k/trackbook/layout/DodgeAbleLayoutBehavior.java
@@ -18,11 +18,13 @@
 package org.y20k.trackbook.layout;
 
 import android.content.Context;
-import android.support.design.widget.CoordinatorLayout;
-import android.support.design.widget.Snackbar;
 import android.util.AttributeSet;
 import android.view.View;
 
+import com.google.android.material.snackbar.Snackbar;
+
+import androidx.coordinatorlayout.widget.CoordinatorLayout;
+
 
 /**
  * DodgeAbleLayoutBehavior class
diff --git a/app/src/main/java/org/y20k/trackbook/layout/NonSwipeableViewPager.java b/app/src/main/java/org/y20k/trackbook/layout/NonSwipeableViewPager.java
index 7a17970..ab5e337 100755
--- a/app/src/main/java/org/y20k/trackbook/layout/NonSwipeableViewPager.java
+++ b/app/src/main/java/org/y20k/trackbook/layout/NonSwipeableViewPager.java
@@ -22,7 +22,6 @@ package org.y20k.trackbook.layout;
  */
 
 import android.content.Context;
-import android.support.v4.view.ViewPager;
 import android.util.AttributeSet;
 import android.view.MotionEvent;
 import android.view.animation.DecelerateInterpolator;
@@ -32,6 +31,8 @@ import org.y20k.trackbook.helpers.LogHelper;
 
 import java.lang.reflect.Field;
 
+import androidx.viewpager.widget.ViewPager;
+
 
 public class NonSwipeableViewPager extends ViewPager {
 
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index 28073d8..c86dec0 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
@@ -8,14 +8,14 @@
     tools:context="org.y20k.trackbook.MainActivity">
 
 
-    <android.support.constraint.ConstraintLayout
+    <androidx.constraintlayout.widget.ConstraintLayout
         android:id="@+id/container"
         android:layout_width="match_parent"
         android:layout_height="match_parent">
 
 
         <!-- BUTTON MY LOCATION -->
-        <android.support.design.widget.FloatingActionButton
+        <com.google.android.material.floatingactionbutton.FloatingActionButton
             android:id="@+id/fabLocationButton"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
@@ -32,7 +32,7 @@
 
 
         <!-- SAVE RESUME -->
-        <android.support.design.widget.FloatingActionButton
+        <com.google.android.material.floatingactionbutton.FloatingActionButton
             android:id="@+id/fabSubMenuButtonSave"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
@@ -47,7 +47,7 @@
             app:layout_constraintStart_toStartOf="@+id/fabSubMenuButtonClear"
             app:srcCompat="@drawable/ic_save_white_24dp" />
 
-        <android.support.v7.widget.CardView
+        <androidx.cardview.widget.CardView
             android:id="@+id/fabSubMenuLabelSave"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
@@ -75,11 +75,11 @@
                 android:textAppearance="@style/TextAppearance.AppCompat.Small"
                 android:textColor="@color/fab_button_card_text"
                 android:textStyle="bold" />
-        </android.support.v7.widget.CardView>
+        </androidx.cardview.widget.CardView>
 
 
         <!-- BUTTON CLEAR -->
-        <android.support.design.widget.FloatingActionButton
+        <com.google.android.material.floatingactionbutton.FloatingActionButton
             android:id="@+id/fabSubMenuButtonClear"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
@@ -94,7 +94,7 @@
             app:layout_constraintStart_toStartOf="@+id/fabSubMenuButtonResume"
             app:srcCompat="@drawable/ic_clear_white_24dp" />
 
-        <android.support.v7.widget.CardView
+        <androidx.cardview.widget.CardView
             android:id="@+id/fabSubMenuLabelClear"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
@@ -122,11 +122,11 @@
                 android:textAppearance="@style/TextAppearance.AppCompat.Small"
                 android:textColor="@color/fab_button_card_text"
                 android:textStyle="bold" />
-        </android.support.v7.widget.CardView>
+        </androidx.cardview.widget.CardView>
 
 
         <!-- BUTTON RESUME -->
-        <android.support.design.widget.FloatingActionButton
+        <com.google.android.material.floatingactionbutton.FloatingActionButton
             android:id="@+id/fabSubMenuButtonResume"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
@@ -141,7 +141,7 @@
             app:layout_constraintStart_toStartOf="@+id/fabMainButton"
             app:srcCompat="@drawable/ic_fiber_manual_record_white_24dp" />
 
-        <android.support.v7.widget.CardView
+        <androidx.cardview.widget.CardView
             android:id="@+id/fabSubMenuLabelResume"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
@@ -168,11 +168,11 @@
                 android:textAppearance="@style/TextAppearance.AppCompat.Small"
                 android:textColor="@color/fab_button_card_text"
                 android:textStyle="bold" />
-        </android.support.v7.widget.CardView>
+        </androidx.cardview.widget.CardView>
 
 
         <!-- MAIN BUTTON -->
-        <android.support.design.widget.FloatingActionButton
+        <com.google.android.material.floatingactionbutton.FloatingActionButton
             android:id="@+id/fabMainButton"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
@@ -189,7 +189,7 @@
 
 
         <!-- BOTTOM NAVIGATION -->
-        <android.support.design.widget.BottomNavigationView
+        <com.google.android.material.bottomnavigation.BottomNavigationView
             android:id="@+id/navigation"
             android:layout_width="0dp"
             android:layout_height="wrap_content"
@@ -214,9 +214,9 @@
             app:layout_constraintTop_toTopOf="parent" />
 
 
-    </android.support.constraint.ConstraintLayout>
+    </androidx.constraintlayout.widget.ConstraintLayout>
 
 
-</android.support.design.widget.CoordinatorLayout>
+</androidx.coordinatorlayout.widget.CoordinatorLayout>
 
 
diff --git a/app/src/main/res/layout/fragment_main_track.xml b/app/src/main/res/layout/fragment_main_track.xml
index cc0d944..9da09f3 100644
--- a/app/src/main/res/layout/fragment_main_track.xml
+++ b/app/src/main/res/layout/fragment_main_track.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<android.support.design.widget.CoordinatorLayout
+<androidx.coordinatorlayout.widget.CoordinatorLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
@@ -29,7 +29,7 @@
     </RelativeLayout>
 
     <!-- BOTTOM SHEET -->
-    <android.support.v4.widget.NestedScrollView
+    <androidx.core.widget.NestedScrollView
         android:id="@+id/statistics_sheet"
         android:layout_width="@dimen/bottom_sheet_width"
         android:layout_height="match_parent"
@@ -37,7 +37,7 @@
         android:background="@color/statistic_sheet_background_collapsed"
         app:behavior_hideable="false"
         app:behavior_peekHeight="54dp"
-        app:layout_behavior="android.support.design.widget.BottomSheetBehavior">
+        app:layout_behavior="com.google.android.material.bottomsheet.BottomSheetBehavior">
 
         <ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
             android:layout_width="match_parent"
@@ -48,6 +48,6 @@
 
         </ScrollView>
 
-    </android.support.v4.widget.NestedScrollView>
+    </androidx.core.widget.NestedScrollView>
 
-</android.support.design.widget.CoordinatorLayout>
\ No newline at end of file
+</androidx.coordinatorlayout.widget.CoordinatorLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/track_management.xml b/app/src/main/res/layout/track_management.xml
index 74928b1..56ce27b 100644
--- a/app/src/main/res/layout/track_management.xml
+++ b/app/src/main/res/layout/track_management.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:id="@+id/track_management_layout"
     android:layout_width="@dimen/bottom_sheet_width"
@@ -57,4 +57,4 @@
         app:srcCompat="@drawable/ic_delete_forever_24dp" />
 
 
-</android.support.constraint.ConstraintLayout>
\ No newline at end of file
+</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/track_statistics.xml b/app/src/main/res/layout/track_statistics.xml
index 121f18f..98cd521 100644
--- a/app/src/main/res/layout/track_statistics.xml
+++ b/app/src/main/res/layout/track_statistics.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:id="@+id/statistics_view"
     android:layout_width="match_parent"
@@ -7,13 +7,13 @@
     android:clickable="true"
     android:focusable="true">
 
-    <android.support.constraint.Group
+    <androidx.constraintlayout.widget.Group
         android:id="@+id/elevation_data"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         app:constraint_referenced_ids="statistics_p_positive_elevation, statistics_data_positive_elevation, statistics_p_negative_elevation, statistics_data_negative_elevation, statistics_p_max_altitude, statistics_data_max_altitude, statistics_p_min_altitude, statistics_data_min_altitude" />
 
-    <android.support.constraint.Group
+    <androidx.constraintlayout.widget.Group
         android:id="@+id/statistics_header"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
@@ -294,4 +294,4 @@
         app:layout_constraintStart_toEndOf="@+id/statistics_p_min_altitude"
         app:layout_constraintTop_toTopOf="@+id/statistics_p_min_altitude" />
 
-</android.support.constraint.ConstraintLayout>
\ No newline at end of file
+</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
diff --git a/app/src/main/res/values-de/strings.xml b/app/src/main/res/values-de/strings.xml
index 7ee2c80..e1dd41c 100644
--- a/app/src/main/res/values-de/strings.xml
+++ b/app/src/main/res/values-de/strings.xml
@@ -45,6 +45,9 @@
     <string name="dialog_export_content_overwrite">Datei existiert bereits. Exportieren und überschreiben Sie diese Aufzeichnung als GPX-Strecke.</string>
     <string name="dialog_export_action_overwrite">Exportieren und überschreiben</string>
     <string name="dialog_share_gpx">GPX-Datei öffnen mit</string>
+    <string name="dialog_error_empty_recording_title">Speichern nicht möglich</string>
+    <string name="dialog_error_empty_recording_content">Trackbook hat noch keine Wegpunkte aufgezeichnet.</string>
+    <string name="dialog_error_empty_recording_action_resume">Aufzeichnung fortsetzen</string>
 
     <!-- toast messages -->
     <string name="toast_message_permissions_granted">Berechtigungen erteilt.</string>
diff --git a/app/src/main/res/values-id/strings.xml b/app/src/main/res/values-id/strings.xml
index d8e146e..0b3394b 100644
--- a/app/src/main/res/values-id/strings.xml
+++ b/app/src/main/res/values-id/strings.xml
@@ -45,6 +45,9 @@
     <string name="dialog_export_content_overwrite">File already exists. Export and overwrite this recording as GPX track.</string>
     <string name="dialog_export_action_overwrite">Export and Overwrite</string>
     <string name="dialog_share_gpx">Share GPX file with</string>
+    <string name="dialog_error_empty_recording_title">Unable to save</string>
+    <string name="dialog_error_empty_recording_content">Trackbook did not record any waypoints so far.</string>
+    <string name="dialog_error_empty_recording_action_resume">Resume Recording</string>
 
     <!-- toast messages -->
     <string name="toast_message_permissions_granted">Permissions granted.</string>
diff --git a/app/src/main/res/values-it/strings.xml b/app/src/main/res/values-it/strings.xml
index 59736fb..361eada 100644
--- a/app/src/main/res/values-it/strings.xml
+++ b/app/src/main/res/values-it/strings.xml
@@ -45,6 +45,9 @@
     <string name="dialog_export_content_overwrite">Il file esiste già. Esportare e sovrascrivere questa registrazione come traccia GPX.</string>
     <string name="dialog_export_action_overwrite">Esporta e sovrascrivi</string>
     <string name="dialog_share_gpx">Share GPX file with</string>
+    <string name="dialog_error_empty_recording_title">Unable to save</string>
+    <string name="dialog_error_empty_recording_content">Trackbook did not record any waypoints so far.</string>
+    <string name="dialog_error_empty_recording_action_resume">Resume Recording</string>
 
     <!-- toast messages -->
     <string name="toast_message_permissions_granted">Permessi acquisiti.</string>
diff --git a/app/src/main/res/values-ja/strings.xml b/app/src/main/res/values-ja/strings.xml
index f8e7d0d..5acf9e6 100644
--- a/app/src/main/res/values-ja/strings.xml
+++ b/app/src/main/res/values-ja/strings.xml
@@ -45,6 +45,9 @@
     <string name="dialog_export_content_overwrite">ファイルは既に存在します。エクスポートし、GPX トラックとしてこの記録を上書きします。</string>
     <string name="dialog_export_action_overwrite">エクスポートして上書き</string>
     <string name="dialog_share_gpx">Share GPX file with</string>
+    <string name="dialog_error_empty_recording_title">Unable to save</string>
+    <string name="dialog_error_empty_recording_content">Trackbook did not record any waypoints so far.</string>
+    <string name="dialog_error_empty_recording_action_resume">Resume Recording</string>
 
     <!-- toast messages -->
     <string name="toast_message_permissions_granted">アクセス許可を付与しました。</string>
diff --git a/app/src/main/res/values-nb-rNO/strings.xml b/app/src/main/res/values-nb-rNO/strings.xml
index 7c717a5..aaca830 100644
--- a/app/src/main/res/values-nb-rNO/strings.xml
+++ b/app/src/main/res/values-nb-rNO/strings.xml
@@ -45,6 +45,9 @@
     <string name="dialog_export_content_overwrite">Fila finnes allerede. Eksporter og overskriv dette opptaket som en GPX-tur.</string>
     <string name="dialog_export_action_overwrite">Eksporter og overskriv</string>
     <string name="dialog_share_gpx">Share GPX file with</string>
+    <string name="dialog_error_empty_recording_title">Unable to save</string>
+    <string name="dialog_error_empty_recording_content">Trackbook did not record any waypoints so far.</string>
+    <string name="dialog_error_empty_recording_action_resume">Resume Recording</string>
 
     <!-- toast messages -->
     <string name="toast_message_permissions_granted">Tilgang gitt.</string>
diff --git a/app/src/main/res/values-nl/strings.xml b/app/src/main/res/values-nl/strings.xml
index 9dce0c1..c953cae 100644
--- a/app/src/main/res/values-nl/strings.xml
+++ b/app/src/main/res/values-nl/strings.xml
@@ -45,6 +45,9 @@
     <string name="dialog_export_content_overwrite">File already exists. Export and overwrite this recording as GPX track.</string>
     <string name="dialog_export_action_overwrite">Export and Overwrite</string>
     <string name="dialog_share_gpx">Share GPX file with</string>
+    <string name="dialog_error_empty_recording_title">Unable to save</string>
+    <string name="dialog_error_empty_recording_content">Trackbook did not record any waypoints so far.</string>
+    <string name="dialog_error_empty_recording_action_resume">Resume Recording</string>
 
     <!-- toast messages -->
     <string name="toast_message_permissions_granted">Rechten verleend.</string>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index f3f6578..3922ab3 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -45,6 +45,9 @@
     <string name="dialog_export_content_overwrite">File already exists. Export and overwrite this recording as GPX track.</string>
     <string name="dialog_export_action_overwrite">Export and Overwrite</string>
     <string name="dialog_share_gpx">Share GPX file with</string>
+    <string name="dialog_error_empty_recording_title">Unable to save</string>
+    <string name="dialog_error_empty_recording_content">Trackbook did not record any waypoints so far.</string>
+    <string name="dialog_error_empty_recording_action_resume">Resume Recording</string>
 
     <!-- toast messages -->
     <string name="toast_message_permissions_granted">Permissions granted.</string>
diff --git a/build.gradle b/build.gradle
index e253631..8daa0e5 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,35 +1,42 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
+
     repositories {
         jcenter()
         google()
     }
-    dependencies {
-        classpath 'com.android.tools.build:gradle:3.1.3'
 
+    dependencies {
+        classpath 'com.android.tools.build:gradle:3.2.1'
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
     }
+
 }
 
 allprojects {
+
     repositories {
         google()
         jcenter()
     }
+
     project.ext {
         applicationId = 'org.y20k.trackbook'
-        versionCode = 28
-        versionName = '1.1.12'
-        minSdkVersion = 22
-        compileSdkVersion = 27
-        targetSdkVersion = 27
-        buildToolsVersion = '27.0.3'
-        supportLibraryVersion = '27.1.1'
-        constraintLayoutVersion = '1.1.0-beta6'
+        versionCode = 29
+        versionName = '1.1.13'
 
-        osmdroidVersion = '6.0.1'
+        compileSdkVersion = 28
+        targetSdkVersion = 27
+        minSdkVersion = 22
+
+        constraintlayoutVersion = '1.1.3'
+        materialVersion = "1.0.0"
+        appcompatVersion = '1.0.0'
+        cardviewVersion = '1.0.0'
+
+        osmdroidVersion = '6.0.2'
         gsonVersion = '2.8.5'
     }
 }
diff --git a/gradle.properties b/gradle.properties
index 1d3591c..915f0e6 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -15,4 +15,6 @@
 # When configured, Gradle will run in incubating parallel mode.
 # This option should only be used with decoupled projects. More details, visit
 # http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects
-# org.gradle.parallel=true
\ No newline at end of file
+# org.gradle.parallel=true
+android.enableJetifier=true
+android.useAndroidX=true
\ No newline at end of file
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 53e5bb2..1952c96 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
-#Wed Apr 04 15:52:45 CEST 2018
+#Thu Oct 04 08:52:03 CEST 2018
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.4-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.10.1-all.zip