It is not always possible to track down each and every issue in the game in the testing or play testing phase. When the game gets bigger, with a huge user base, then it is more likely that unknown issues will be exposed. Google Analytics helps in these fields, not only with the current behavior of the user, but with the game performance as well.

Google Analytics is mostly used to track game events. So, the tracking events must be decided very carefully. The triggering points must also be placed in a strategic way. The developer might not require all the events and behavior data. More tracking may be even harmful to the application, as there would be more data use and more processing in the game.

The developer should always prioritize events. Events should be tracked based on the game flow design. They should then be validated by user action.

From the monetization point of view, it should always be a priority to track when the user is hitting the pay wall or which section is being visited more. A simple advertisement in the most visited section may increase the application's revenue.

The best utilization of the Google Analytics tool is no different than any other Android application analytics tool. This tool is the best possible way to track user movement, and through the data the developer can easily predict the user's motive or intention with the game.

Let's have a quick look at the three purchasable options in Google IAB. We will have a detailed look at them later in this chapter:

Google Play Services comes with IAB APIs. The developer needs to register the application on Google Play Store to get live access. This system works with item IDs, which are called SKUs. Each SKU represents an item in the Play Store. The developer may not use all the SKUs created in the Google Play account for a particular game.

We have already noted that Google IAB provides a platform to implement a direct digital purchasing system within the application. This saves great effort and time for both developers and consumers. Let's have a quick look at the advantages of Google IAB:

So far, Google IAB has proved to be an excellent system for both developers and consumers or users. However, there are several sectors where Google IAB is still lagging behind. Now, let's have look at the sectors where Google IAB needs to improve:

Despite these issues, Google IAB is still the most popular platform for billing for Android developers. Google has started including carrier billing services within Google IAB, which may prove to be the most significant feature.

Having a leaderboard integrated in games is always a plus, as it helps users compete with each other even when the game is not multiplayer. It is human psychology to try to become superior to others. Using this feature, there can be more user engagement than usual. However, the competing criteria on the leaderboard must be chosen carefully.

A good example of a leaderboard-driven game is Candy Crush. Users are very active, playing the simple game to stay ahead of their friends on the leaderboard.

There is no separate Google Leaderboard package. This can be included by integrating Google Play Services itself. However, Leaderboard has to be set up in the Google games account to use it.

The developer can choose any parameter or calculation to store leaderboard data. Google Leaderboard supports data from multiple leaderboards for a single game. Most of the developers use this feature efficiently to show different leader lists, depending on the time period, region, or some other customized parameter.

Primary variations of Google Leaderboard are of two types:

Leaderboard storage can be classified into two types, based on ascending and descending order. In terms of Google Leaderboard, they are called:

A score is always a numeric value, which is again classified into three formats:

In the case of a numeric value, the developer can specify the decimal placement. In the case of the time format, the developer needs to pass the score in milliseconds, and it will be automatically interpreted in the hh:mm:ss format. In the case of the currency format, the developer needs to specify the currency and its unit value beforehand. The Leaderboard will only take values in a unit and convert it to the specified unit format.

Leaderboard can have unique icons to display or indicate a unique leaderboard.

The database stores the registration details of a client or target device with the GCM service. So, each device is required to register only once. The same details are used to send push notifications to the registered target devices.

Developers need to put up a server to achieve and control push notifications.

A target or client device is the platform where the message is pushed from the GCM. Each target device has a unique registration ID through the GCM. Without registration, a target device cannot receive any notifications.

The GCM service is responsible for registering devices and pushing messages to them. The server requests the GCM service with a list of registration IDs and customized messages. GCM is only responsible for pushing the given content to specified devices:

Integrating push notifications is done in three steps:

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
<permission android:name="com.example.gcm.permission.C2D_MESSAGE"
        android:protectionLevel="signature" />
<uses-permission android:name="com.example.gcm.permission.C2D_MESSAGE" />

<receiver android:name="com.google.android.gms.gcm.GcmReceiver"
            android:exported="true" android:permission="com.google.android.c2dm.permission.SEND" >
<intent-filter>
<action android:name="com.google.android.c2dm.intent.REGISTRAION" />
<action android:name="com.google.android.c2dm.intent.RECEIVE" />
<category android:name="com.example.gcm" />
      </intent-filter>
</receiver>
<service android:name=".GcmService" android:exported="false">
      <intent-filter>
<action android:name="com.google.android.c2dm.intent.RECEIVE" />
      </intent-filter>
</service>

private final Context testContext = this;
private final String SENDER_ID = "<Application ID from Google developer console>";
private final String SHARED_PREF = "com.test.gcmclient_preferences";
private final String GCM_TOKEN = "testgcmtoken";

SharedPreferences appPrefs = testContext.getSharedPreferences(SHARED_PREF, Context.MODE_PRIVATE);
String token = appPrefs.getString(GCM_TOKEN, "");
if (token.isEmpty()) 
{
  try 
  {
    InstanceID instanceID =  InstanceID.getInstance(testContext);
    token = instanceID.getToken(SENDER_ID,  GoogleCloudMessaging.INSTANCE_ID_SCOPE, null);
    if (token != null && !token.isEmpty()) 
    {
      SharedPreferences.Editor prefsEditor = appPrefs.edit();
      prefsEditor.putString(GCM_TOKEN, token);
      prefsEditor.apply();
    }
  }
  catch (Exception e) 
  {
    e.printStackTrace();
  }
}

public class GcmService extends GcmListenerService 
{
  @Override
  public void onMessageReceived(String from, Bundle data) 
  {
    JSONObject jsonObject = new JSONObject();
    Set<String> keys = data.keySet();
    for (String key : keys) 
    {
      try 
      {
        jsonObject.put(key, data.get(key));
      } 
      catch (JSONException e) 
      {
        e.printStackTrace();
      }
    }
    try 
    {
      sendNotification("Received: " + jsonObject.toString(5));
    } 
    catch (JSONException e) 
    {
      e.printStackTrace();
    }
  }

  @Override
  public void onDeletedMessages() 
  {
    Log.d("Message is deleted …");
  }

  @Override
  public void onMessageSent(String msgId) 
  {
    Log.d("Message is sent …" + msgId);
  }

  @Override
  public void onSendError(String msgId, String error) 
  {
    Log.d("Sending Error … Msg" + msgId);
    Log.d("Error …" + error);
  }
  private void sendNotification(final String msg) 
  {
    Log.d("Sending Msg …" + msg);
  }
}

Push notifications are an inevitable part of modern day game development. Push notifications are used for the following reasons: