Chapter 2. Create your first app


Are you ready to start building your first app? Before you start, make sure you’ve followed the instructions in chapter 1 to set up your programming environment!

This chapter covers

  • Creating a simple app
  • Testing your app and seeing it run
  • Knowing what a user interface is and why you should care about it

You’re now all set to cover your second milestone: create your first app. If you have your own iDevice, you’ll be able to run your app on it. If you don’t, you’ll still be able to run it by using a simulator. Let’s go ahead!

Hello apps!

You’ve reached the first stop on your journey. You’ve installed Xcode, the app-building software, and you’re ready to go.

In this chapter, you travel to your next location and build your first simple app along the way. You learn how to create a simple app that can run on an iPhone or iPad. You learn how to try out the apps you create by using a special program called a simulator. And before you’re done, you’ll get some design tips for making apps that you and your users will like even more.

When I say iDevice, I mean an iPhone or an iPad. It’s just a quick way to say “any Apple device that runs iOS apps.”

Your first app: Hello World!

It’s time for you to build your first app!

There’s a tradition that the first program you learn to write in any programming language displays the words Hello World! on the screen. Your first app does the same thing, displaying Hello World! on the screen of an iDevice.

Discover the user interface

Designing good UIs

Try this app on your own

Test your app knowledge