You must sign up for a free account on http://back4app.com in order to create a App on back{4}app, grab its App and Client Keys and paste them the Configs.swift file of this app.

back{4}app service offers the following FREE features for the STARTER pack:
• 1 GB Database Storage
• 5 GB File Storage
• 10 Requests/second
• 50 K Requests/month
• 1 Cloud Code Job

Check out its PRICING tables here: https://www.back4app.com/pricing/

Here you can find DOCS: http://docs.back4app.com/

Read this tutorial to learn how to rename a package name in Android Studio: https://hubpages.com/technology/Android-How-to-rename-an-app-package

1. enter the .xml files where there’s an AdView and remove its code:

       <com.google.android.gms.ads.AdView
           android:id="@+id/admobBanner" 
           android:layout_width="wrap_content" 
           android:layout_height="wrap_content" 
           ads:adSize="BANNER" 
           ads:adUnitId="@string/ADMOB_BANNER_UNIT_ID" 
           android:layout_alignParentBottom="true" 
           android:layout_centerHorizontal="true">
       </com.google.android.gms.ads.AdView>
   

2. Enter the .java files where there’s an AdRequest instance into its onCreate() method and remove its code:

           // Init AdMob banner
           AdView mAdView = (AdView) findViewById(R.id.admobBanner);
           AdRequest adRequest = new AdRequest.Builder().build();
           mAdView.loadAd(adRequest);
   

3. Lastly, remove the play-services-ads reference in the build.gradle file:

       compile 'com.google.android.gms:play-services-ads:+'