1. Introduction

Welcome to this tutorial where we will be discussing how to add in-app purchases and ads to your mobile application. In-app purchases are a popular way to monetize apps by allowing users to buy special features or digital goods within an app. Ads, on the other hand, provide revenue each time they are displayed or interacted with by a user.

By the end of this tutorial, you will have learned:
- What in-app purchases and ads are
- How to integrate in-app purchases into your app
- How to integrate ads into your app

Prerequisites:
- Basic knowledge of mobile app development
- An integrated development environment (IDE) like Android Studio or Xcode
- A basic understanding of Google AdMob for ads (If not, don't worry, we'll cover it!)

2. Step-by-Step Guide

In-App Purchases

1. Setting up the Storefront: Here, you'll be defining what items you want to sell in your app. These can be consumables (one-time use items), non-consumables (permanent items), or subscriptions.

2. Coding the Purchase Flow: This is where you'll write the code to handle the purchase process. This includes initiating the purchase, processing the payment, and providing the item to the user.

3. Testing your In-App Purchases: Before releasing your app, you should thoroughly test the purchase flow to ensure that everything works as expected.

Ads

1. Choosing the Ad Format: AdMob provides several ad formats including banner, interstitial, and rewarded ads. Choose the one that best fits your app's user experience.

2. Integrating the AdMob SDK: You'll need to set up the SDK in your project to start displaying ads.

3. Displaying Ads: Here, you'll write the code to display ads at desired locations in your app.

4. Testing your Ads: Again, testing is crucial. Make sure your ads display properly and don't negatively impact the user experience.

3. Code Examples

Due to the complexity and length of the code, we aren't able to provide full examples here. However, you can find detailed code examples in the official documentation for In-App Purchases and Google AdMob.

4. Summary

In this tutorial, we have explained how to integrate in-app purchases and ads into a mobile application. In-app purchases allow you to sell digital goods or features within your app, while ads can generate revenue each time they are displayed or interacted with by a user.

For continued learning, you should:
- Familiarize yourself more with the Google AdMob policies and best practices
- Learn more about testing your in-app purchases and ads
- Experiment with different ad formats and in-app purchase types

5. Practice Exercises

1. Exercise 1: Create an app with a single in-app purchase. This could be a simple feature unlock or a virtual good.

2. Exercise 2: Add a banner ad to the bottom of your app. Test it using the AdMob test ad units.

3. Exercise 3: Add an interstitial ad that displays at a certain point in your app's flow. Again, test it using the AdMob test ad units.

Solutions to these exercises will vary greatly depending on your specific app and its functionalities. However, the general principles and steps covered in this tutorial should guide you towards the right direction.

Remember, practice is key in mastering these concepts. Happy coding!