To develop an application for iOS, you should start with an application called Xcode. There are other alternative tools you can use, but Xcode is Apple's official tool. Note, however, that it only runs on macOS. The latest official version is Xcode 8.3.3 with Xcode 9 (currently in beta) due to be released later this year.
Boot up your Mac and install Xcode from the App Store if it's not already installed.
(If you prefer not to use the App Store or have problems, you can also download Xcode from the Apple Developer website, but make sure that you select the latest release version and not a beta version.)
Open Xcode. The following window will open:
The window presents you with the following options:
Select the second option Create a new Xcode project and Xcode will ask you to do some initial project setup:
This wizard is used to select your project template. There are 5 options:
You can see that there are many different templates for your application. These templates are helpful to boost your development; they are pre-built with some basic project setups like UI interfaces and class files.
Here, we'll use the first option, iOS.
This template contains a combined master and detail interface: the master contains objects which are related to the detail interface. Selecting objects in the master will change the details interface. You can see this kind UI in the Settings, Notes and Contacts applications on the iPad.
This template is used to create the page-based application. Pages are different views held by one container.
Single View Application:
This is a normal application development template. This is good for beginners to learn application flow.
This template creates tabs at the bottom part of an application. Each tab has a different UI and a different navigation flow. You can see this template used in apps like Clock, iTunes Store, iBooks and App Store.
This is a starting point for game development. You can go further with game technologies like SceneKit, SpriteKit, OpenGL ES and Metal.
In this example, we will start with Single View Application
The wizard helps you to define project properties:
.xcdatamodel. You can also add this file later on if you don't know in advance.
Click on Next and it will ask you for a location where you want to create project directory.
Click on Create and you will see the Xcode UI with an already defined project setup. You can see some classes and Storyboard files.
This is a basic template for a Single View Application.
At the top left of the window, check that a simulator is selected (e.g. "iPhone 6" as shown here) and then press the triangular RUN button.
A new application will open—Simulator (this may take some time the first time you run it and you may need to try twice if you see an error the first time). This application provides us with device simulation for created applications. It almost looks like a real device! It contains some applications like a real device. You can simulate orientations, location, shake gesture, memory warnings, In-Call Status bar, finger touch, lock, reboot, home etc.
You will see a plain white application because we have not made any changes to the template yet.
So start your own. it’s a long run and there are lots of new opportunities waiting for you!
If you are not sure where to go next, try out Apple's 'Jump Right In' tutorial. You have already performed the first few steps so are off to a head start.