Automatic versioning (versionName and versionCode) using GIT.

src/main/res/layout/about.xml

@@ -33,7 +33,15 @@
     <View style="@style/StatsHorizontalLine" />
 
     <TextView
-        android:id="@+id/about_text_version"
+        android:id="@+id/about_text_version_name"
+        style="@style/TextSmall"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:gravity="center"
+        android:padding="6dp" />
+
+    <TextView
+        android:id="@+id/about_text_version_code"
         style="@style/TextSmall"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"

src/main/res/values/strings.xml

@@ -24,8 +24,11 @@ limitations under the License.
   <string name="about_url" translate_description="In the about activity, the URL to the source code repository.">
     Project web page: <a href="%1$s">%1$s</a>
   </string>
-  <string name="about_version" translate_description="In the about activity, the version of the source code (i.e., Android's versionName).">
-    Version: %1$s
+  <string name="about_version_name" translate_description="In the about activity, the version of the source code (i.e., Android's versionName).">
+    Version name: %1$s
+  </string>
+  <string name="about_version_code" translate_description="In the about activity, the version of the source code (i.e., Android's versionName).">
+    Version code: %1$d
   </string>
   <string name="about_history" translatate_description="In the about activity, the relationship with MyTracks.">
     OpenTracks is a fork of <a href="https://code.google.com/archive/p/mytracks/"><i>Google\'s MyTracks</i></a> (discontinued in 2016).

src/main/res/xml/settings.xml

@@ -38,7 +38,7 @@ limitations under the License.
     <Preference
         android:title="@string/about_preference_title">
         <intent
-            android:targetPackage="de.dennisguse.opentracks"
+            android:targetPackage="@string/applicationId"
             android:targetClass="de.dennisguse.opentracks.AboutActivity" />
     </Preference>
 </PreferenceScreen>