diff --git a/app/build.gradle b/app/build.gradle
index 50060bc..3146d24 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -30,7 +30,7 @@ android {
     }
     buildTypes {
         release {
-            minifyEnabled false
+            minifyEnabled true
             proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
         }
     }
diff --git a/app/src/main/java/pl/tpolgrabia/urbanexplorer/callbacks/StandardLocationListener.java b/app/src/main/java/pl/tpolgrabia/urbanexplorer/callbacks/StandardLocationListener.java
index fe789c7..87f05d2 100644
--- a/app/src/main/java/pl/tpolgrabia/urbanexplorer/callbacks/StandardLocationListener.java
+++ b/app/src/main/java/pl/tpolgrabia/urbanexplorer/callbacks/StandardLocationListener.java
@@ -14,7 +14,6 @@ import java.util.List;
  */
 public class StandardLocationListener implements LocationListener {
     private static final Logger lg = LoggerFactory.getLogger(StandardLocationListener.class);
-    private static final String CLASS_TAG = StandardLocationListener.class.getSimpleName();
     private List<StandardLocationListenerCallback> locationChangedCallbacks = new ArrayList<>();
 
     @Override