diff --git a/app/src/main/java/fr/free/nrw/commons/AboutActivity.java b/app/src/main/java/fr/free/nrw/commons/AboutActivity.java
index 0ef5fa171..6ed1bba1d 100644
--- a/app/src/main/java/fr/free/nrw/commons/AboutActivity.java
+++ b/app/src/main/java/fr/free/nrw/commons/AboutActivity.java
@@ -8,10 +8,18 @@ import butterknife.ButterKnife;
 import fr.free.nrw.commons.theme.NavigationBaseActivity;
 import fr.free.nrw.commons.ui.widget.HtmlTextView;
 
+/**
+ * Represents about screen of this app
+ */
 public class AboutActivity extends NavigationBaseActivity {
     @BindView(R.id.about_version) TextView versionText;
     @BindView(R.id.about_license) HtmlTextView aboutLicenseText;
 
+    /**
+     * This method helps in the creation About screen
+     *
+     * @param savedInstanceState Data bundle
+     */
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
diff --git a/app/src/main/java/fr/free/nrw/commons/CommonsApplication.java b/app/src/main/java/fr/free/nrw/commons/CommonsApplication.java
index 9a7b94a99..c2da8ad98 100644
--- a/app/src/main/java/fr/free/nrw/commons/CommonsApplication.java
+++ b/app/src/main/java/fr/free/nrw/commons/CommonsApplication.java
@@ -44,21 +44,32 @@ import timber.log.Timber;
 )
 public class CommonsApplication extends DaggerApplication {
 
+    public static final String DEFAULT_EDIT_SUMMARY = "Uploaded using Android Commons app";
+    public static final String FEEDBACK_EMAIL = "commons-app-android@googlegroups.com";
+    public static final String LOGS_PRIVATE_EMAIL = "commons-app-android-private@googlegroups.com";
+    public static final String FEEDBACK_EMAIL_SUBJECT = "Commons Android App (%s) Feedback";
     @Inject SessionManager sessionManager;
     @Inject DBOpenHelper dbOpenHelper;
     @Inject @Named("default_preferences") SharedPreferences defaultPrefs;
     @Inject @Named("application_preferences") SharedPreferences applicationPrefs;
     @Inject @Named("prefs") SharedPreferences otherPrefs;
-
-    public static final String DEFAULT_EDIT_SUMMARY = "Uploaded using Android Commons app";
-
-    public static final String FEEDBACK_EMAIL = "commons-app-android@googlegroups.com";
-    public static final String LOGS_PRIVATE_EMAIL = "commons-app-android-private@googlegroups.com";
-    public static final String FEEDBACK_EMAIL_SUBJECT = "Commons Android App (%s) Feedback";
-
     private CommonsApplicationComponent component;
     private RefWatcher refWatcher;
 
+    /**
+     * Provides a way to get member refWatcher
+     *
+     * @param context Application context
+     * @return application member refWatcher
+     */
+    public static RefWatcher getRefWatcher(Context context) {
+        CommonsApplication application = (CommonsApplication) context.getApplicationContext();
+        return application.refWatcher;
+    }
+
+    /**
+     * Used to declare and initialize various components and dependencies
+     */
     @Override
     public void onCreate() {
         super.onCreate();
@@ -80,6 +91,10 @@ public class CommonsApplication extends DaggerApplication {
         System.setProperty("in.yuvi.http.fluent.PROGRESS_TRIGGER_THRESHOLD", "3.0");
     }
 
+    /**
+     * Helps in setting up LeakCanary library
+     * @return instance of LeakCanary
+     */
     protected RefWatcher setupLeakCanary() {
         if (LeakCanary.isInAnalyzerProcess(this)) {
             return RefWatcher.DISABLED;
@@ -87,16 +102,19 @@ public class CommonsApplication extends DaggerApplication {
         return LeakCanary.install(this);
     }
 
-    public static RefWatcher getRefWatcher(Context context) {
-        CommonsApplication application = (CommonsApplication) context.getApplicationContext();
-        return application.refWatcher;
-    }
-
+    /**
+     * Helps in injecting dependency library Dagger
+     * @return Dagger injector
+     */
     @Override
-     protected AndroidInjector<? extends DaggerApplication> applicationInjector() {
+    protected AndroidInjector<? extends DaggerApplication> applicationInjector() {
         return injector();
     }
 
+    /**
+     * used to create injector of application component
+     * @return Application component of Dagger
+     */
     public CommonsApplicationComponent injector() {
         if (component == null) {
             component = DaggerCommonsApplicationComponent.builder()
@@ -106,6 +124,11 @@ public class CommonsApplication extends DaggerApplication {
         return component;
     }
 
+    /**
+     * clears data of current application
+     * @param context Application context
+     * @param logoutListener Implementation of interface LogoutListener
+     */
     public void clearApplicationData(Context context, LogoutListener logoutListener) {
         File cacheDirectory = context.getCacheDir();
         File applicationDirectory = new File(cacheDirectory.getParent());
@@ -145,6 +168,9 @@ public class CommonsApplication extends DaggerApplication {
         Contribution.Table.onDelete(db);
     }
 
+    /**
+     * Interface used to get log-out events
+     */
     public interface LogoutListener {
         void onLogoutComplete();
     }
diff --git a/build.gradle b/build.gradle
index 6b7e5dc00..b0e8b6718 100644
--- a/build.gradle
+++ b/build.gradle
@@ -7,7 +7,7 @@ buildscript {
         google()
     }
     dependencies {
-        classpath "com.android.tools.build:gradle:${project.gradleVersion}"
+        classpath 'com.android.tools.build:gradle:3.0.1'
         classpath 'com.dicedmelon.gradle:jacoco-android:0.1.1'
         classpath 'com.getkeepsafe.dexcount:dexcount-gradle-plugin:0.7.1'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"