The iPhone operating system is referred to as IOS for short. It's Apple's mobile operating system for their handheld devices. It is compatible with the programming languages Objective-C, C, and Swift. It runs on the Macintosh OS X operating system.

It is the second most popular mobile operating system in the world, following Android. This operating system is used by many Apple mobile devices, such as the iPhone, iPad, and iPod.

iOS uses a multi-touch UI to control the device, such as swiping your finger on the screen to progress to the next page or pressing your fingertips to expand in and out.

The iOS gadgets are updated frequently, and you've found that at least one new iPhone or iPad edition is released every year. The number of iPhone/iPad users has risen dramatically. Developers can generate money by producing apps for the iPhone and iPad as a result of this. Apple's App Store is a place where you may download apps.

You need to have a fundamental understanding of software coding terminologies before starting this lesson. Familiarity with any computer language, particularly Objective C, will aid you in learning the concepts of iOS programming more quickly.

IOS Environment Setup

It's preferable to keep your iOS apps in different settings, especially if they're connecting with any services. Assume an iOS app with three different web backend environments to choose from: development, staging, and production.

What's the best approach to use these multiple servers in the iOS app?

The simplest method is to create a file in the native language, such as Swift, to store these environment variables as strings or other constants. However, this could lead to various issues, including security concerns and general bad practices such as hardcoding flag values or relying on macros. Instead, you can utilise separate files that you won't have to check into version control and explicitly specify the app's attributes that will change based on the environment.