diff --git a/AirKoality/app/app.iml b/AirKoality/app/app.iml
index 60b7707..b101fa9 100644
--- a/AirKoality/app/app.iml
+++ b/AirKoality/app/app.iml
@@ -89,7 +89,6 @@
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/apk_list" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/blame" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/build-info" />
-      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/builds" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/bundle_manifest" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/check_manifest_result" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/compatible_screen_manifest" />
@@ -97,12 +96,10 @@
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/incremental" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/incremental-runtime-classes" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/incremental-verifier" />
-      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/instant-run-apk" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/instant_app_manifest" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/instant_run_app_info_output_file" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/instant_run_main_apk_resources" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/instant_run_merged_manifests" />
-      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/instant_run_split_apk_resources" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/javac" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/manifest-checker" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/merged_assets" />
@@ -177,6 +174,7 @@
     <orderEntry type="library" name="Gradle: com.android.support:viewpager:28.0.0@aar" level="project" />
     <orderEntry type="library" name="Gradle: android.arch.persistence.room:common:1.1.1@jar" level="project" />
     <orderEntry type="library" name="Gradle: com.google.android.gms:play-services-basement:16.0.1@aar" level="project" />
+    <orderEntry type="library" name="Gradle: com.google.maps.android:android-maps-utils:0.5@aar" level="project" />
     <orderEntry type="library" scope="TEST" name="Gradle: org.hamcrest:hamcrest-integration:1.3@jar" level="project" />
     <orderEntry type="library" scope="TEST" name="Gradle: org.hamcrest:hamcrest-library:1.3@jar" level="project" />
     <orderEntry type="library" name="Gradle: android.arch.lifecycle:common:1.1.1@jar" level="project" />
diff --git a/AirKoality/app/build.gradle b/AirKoality/app/build.gradle
index 328516d..177e6e2 100644
--- a/AirKoality/app/build.gradle
+++ b/AirKoality/app/build.gradle
@@ -30,6 +30,7 @@ dependencies {
     implementation 'com.android.support:design:28.0.0'
     implementation 'com.android.support:support-v4:28.0.0'
     implementation 'com.google.android.gms:play-services-maps:16.1.0'
+    implementation 'com.google.maps.android:android-maps-utils:0.5+'
     implementation 'android.arch.persistence.room:runtime:1.1.1'
     implementation 'com.google.android.gms:play-services-location:16.0.0'
     annotationProcessor 'android.arch.persistence.room:compiler:1.1.1'
diff --git a/AirKoality/app/src/main/java/at/fhj/airkoality/model/MapClusterItem.java b/AirKoality/app/src/main/java/at/fhj/airkoality/model/MapClusterItem.java
new file mode 100644
index 0000000..749062c
--- /dev/null
+++ b/AirKoality/app/src/main/java/at/fhj/airkoality/model/MapClusterItem.java
@@ -0,0 +1,33 @@
+package at.fhj.airkoality.model;
+
+import com.google.android.gms.maps.model.LatLng;
+import com.google.maps.android.clustering.ClusterItem;
+
+public class MapClusterItem implements ClusterItem {
+
+
+    private LatLng position;
+    private String titel;
+    private String snippet;
+
+    public MapClusterItem(LatLng position, String titel, String snippet) {
+        this.position = position;
+        this.titel = titel;
+        this.snippet = snippet;
+    }
+
+    @Override
+    public LatLng getPosition() {
+        return position;
+    }
+
+    @Override
+    public String getTitle() {
+        return titel;
+    }
+
+    @Override
+    public String getSnippet() {
+        return snippet;
+    }
+}
diff --git a/AirKoality/app/src/main/java/at/fhj/airkoality/ui/fragment/MapFragment.java b/AirKoality/app/src/main/java/at/fhj/airkoality/ui/fragment/MapFragment.java
index 6d290d9..e2189e6 100644
--- a/AirKoality/app/src/main/java/at/fhj/airkoality/ui/fragment/MapFragment.java
+++ b/AirKoality/app/src/main/java/at/fhj/airkoality/ui/fragment/MapFragment.java
@@ -17,13 +17,14 @@ import com.google.android.gms.maps.MapView;
 import com.google.android.gms.maps.OnMapReadyCallback;
 import com.google.android.gms.maps.model.LatLng;
 import com.google.android.gms.maps.model.Marker;
-import com.google.android.gms.maps.model.MarkerOptions;
+import com.google.maps.android.clustering.ClusterManager;
 
 import java.util.List;
 
 import at.fhj.airkoality.R;
 import at.fhj.airkoality.db.room.AirKoalityDB;
 import at.fhj.airkoality.model.Location;
+import at.fhj.airkoality.model.MapClusterItem;
 import at.fhj.airkoality.ui.activity.MeasurementActivity;
 
 public class MapFragment extends Fragment implements OnMapReadyCallback, GoogleMap.OnInfoWindowClickListener {
@@ -31,6 +32,7 @@ public class MapFragment extends Fragment implements OnMapReadyCallback, GoogleM
     private MapView mapView;
     private GoogleMap map;
     private AirKoalityDB database;
+    private ClusterManager<MapClusterItem> clusterManager;
 
     @Nullable
     @Override
@@ -64,15 +66,14 @@ public class MapFragment extends Fragment implements OnMapReadyCallback, GoogleM
             new Thread(() -> {
                 List<Location> locations = database.locationDAO().getAll();
                 getActivity().runOnUiThread(() -> {
-                    map.clear();
+                    clusterManager.clearItems();
                     for (Location location : locations) {
-                        MarkerOptions markerOptions = new MarkerOptions()
-                                .title(location.getLocation())
-                                .snippet(location.getCity() + ", " + location.getCountry())
-                                .position(new LatLng(location.getLatitude(), location.getLongitude()));
+                        MapClusterItem item = new MapClusterItem(new LatLng(location.getLatitude(), location.getLongitude()),location.getLocation(),location.getCity() + ", " + location.getCountry());
 
-                        map.addMarker(markerOptions);
+
+                        clusterManager.addItem(item);
                     }
+                    clusterManager.cluster();
                 });
             }).start();
         }
@@ -86,6 +87,10 @@ public class MapFragment extends Fragment implements OnMapReadyCallback, GoogleM
         map = googleMap;
         map.setOnInfoWindowClickListener(this);
         enableMyLocation();
+
+        clusterManager = new ClusterManager<>(getContext(), map);
+        map.setOnCameraIdleListener(clusterManager);
+        map.setOnMapClickListener(clusterManager);
     }
 
 
diff --git a/README.md b/README.md
index 4c7bdbc..c876961 100644
--- a/README.md
+++ b/README.md
@@ -92,4 +92,9 @@ Notifications benötigen immer einen Channel und Channel ID (ab Android O verfü
 
 ## 17.05.2019 - Online
 
-## 18.05.2019 - Online
\ No newline at end of file
+Map Fragment implementiert
+
+
+## 18.05.2019 - Online
+
+Clustering von Map Fragment um Performance der App zu optimieren -> Je nach Zoomfaktor werden MapMarker gruppiert.
\ No newline at end of file