iOS App Development Guide

Setting up your development environment

If you’re an iOS rookie, you first need to prepare your development environment and install all the tools you’re going to need to build iOS applications going forward. These are the main things you will need to do:

• Have Mac computer with the latest version of the MacOS operating system. Apple keeps updating its operating systems and tools and you want to ensure you’ve got the latest version downloaded, otherwise you may miss out on crucial features.
• Install Xcode, Apple’s integrated development environment (IDE). This provides your central command centre for building, testing and debugging iOS apps. We love Xcode for its simple, user-friendly interface and the breadth of its toolkit, which will add real agility to your development process.
• Register as an Apple Developer. Once you’re registered, you’ll have insider access to a galaxy of resources, documentation, and tools tailored specifically to creating exceptional apps for Apple devices. Not only does this give you insider knowledge and support, it also allows you to distribute your apps on the App Store and even monetize them through in-app purchases or subscriptions.

Once the environment is up and running, you can really start to tackle the world of iOS App development. In the rest of this article, you’ll find a handy suite of resources, insightful articles, tutorials, and guides from our blog, taking you from entry to expert level.

iOS app development fundamentals

The journey to become an expert iOS developer should start learning the building blocks of your new craft and to grasp the basic architecture of an iOS app. It’s vital to start checking out Apple’s user interface guidelines and then get up to speed with tools like Git or iPhone Simulator.

One of the initial steps in creating your app is deciding on your mobile app architecture, as it can significantly influence your approach to mobile app development. It’s important to understand each of the architecture options available to ensure your code is future-proof and aligns with your business needs.

Also, take a look at existing libraries that might help you in the process of crafting your application, you can save a lot of time leveraging some of these libraries.

Coding in Swift

Swift has become the first language of iOS development, and is now the standard form across iOS, macOS, watchOS, and tvOS development. You’ll love the elegance of its syntax, the breadth of its libraries and the efficiency baked into its type system. Like all new languages, it takes a bit of getting used to, but the more you practice, the better you’ll become.

Swift has become the primary language for iOS development, now serving as the standard across iOS, macOS, watchOS, and tvOS development. You’ll appreciate the elegance of its syntax, the breadth of its libraries, and the efficiency ingrained in its type system. Like all new languages, it requires some adjustment, but with practice, you’ll become more proficient.

When you begin writing in Swift, it’s crucial to familiarize yourself with some of the language’s basic concepts. An excellent resource provided by Apple is The Swift Programming Language book.

Once you’ve grasped the basics of Swift, you’re ready to delve into some of its powerful and incredibly useful features. Understanding how closures work will add significant flexibility to your code. Coupled with Swift Generics, you’ll equip yourself with a highly potent toolbox as a developer.

Later, focus on the always essential features of any language that you’ll use daily. Start by learning how to effectively manage Dates and Times in Swift; then, explore the details of data storage structures within Swift. Begin with an overview of all Swift collection data structures, moving into the specifics of the most commonly used structure: arrays. If you want to take the most of this data structures, you can check how Swift Standard Library Protocols work to add them to your custom objects.

Using SwiftUI

SwiftUI is Apple’s central framework for building user interfaces, and its cross-platform compatibility ensures a consistent user experience across Apple devices. You’ll love the balance between its robust pre-built elements and the creative possibilities provided by its customizations. With SwiftUI you can easily create input forms to gather the required information from your users. Probably your form will have a button, so you can check-out how to add and style your SwiftUI buttons.

In addition to buttons and text fields, SwiftUI pickers are indispensable when it comes to creating forms. Pickers provide a user-friendly way to select from a list of options, making them perfect for settings, preferences, or any other selection-based input. SwiftUI offers various picker styles, including menu, segmented control, and wheel, allowing you to choose the most appropriate style for your app’s design and user experience.

Dealing with Data Persistence

When creating your iOS app, it’s crucial to consider all possible places and conditions where your app will be used. There will be situations where network connectivity is limited, so planning to add a data persistence layer to your application is essential.

There are multiple technologies you can use to add storage features to your app. The most basic ones allow you to store basic user data. These features include UserDefaults, Keychain, and FileManager, which enable you to store basic data on the device.

If you require more advanced data storage, you then need to use a proper database. On iOS devices, you have multiple options. If you prefer raw SQL, you can directly use SQLite in your app. A more flexible approach, especially if you are building multi-platform or multi-device applications, is to use Realm. This allows you to implement a storage layer that can easily sync the data to the cloud.

If you prefer to stay with Apple’s recommended data persistence frameworks, you can take advantage of the new SwiftData framework or use the proven and powerful Core Data framework.

Advanced iOS topics

Once you’ve grasped the fundamentals, it’s time for the really fun bit: mastering advanced iOS technologies and exploring the limits of your creativity. Now you can tackle highly sophisticated features including push notifications, in-app purchases and geofencing: these will aid your marketing and monetization strategies, and give you a crucial edge in the highly competitive iOS marketplace.

You can also explore new iOS features like iOS App Clips that allows customers to allow users to quickly access a specific feature within an application without downloading the full app. Another hot topic is AI and Machine Learning which can make you stand out in the crowd.

iOS networking

iOS Networking is a very important topic you should master as an iOS app developers. Networking allows your app to get dynamic content, enabling users to see the latest data as activity is saved to a remote database using web APIs, from where it can be fetched and viewed by users on other devices. And as probably your app is not an isolated entity will need to communicate to some server to using some Rest API or GraphQL API; if you are building a new application from scratch, GraphQL might be the best option at the moment, allowing to write more efficent data-drive applications.

If you are creating an application that demands real-time data, such as chat applications, financial apps, or when receiving data from IoT devices, your best option would be to use the WebSocket protocol instead of making traditional HTTP requests.

iOS App testing, QA and distribution

Just one final step left, but it’s crucial: learning how to publish your app efficiently and reliably. To be able to publish a high-quality app, you must test your app properly and be ready to provide customer support to your users, no matter their device, location or edge case.

As an iOS developer, writing proper unit tests can make the difference between a very buggy app and a properly functional one. Additionally, integrating a code analysis tool into your workflow and establishing a robust development process will increase your confidence when releasing your app, greatly enhancing your peace of mind. Automate all these tasks as much as possible: automating your app builds and taking advantage of automated testing tools can save you a ton of time and money.

Remember: bugs are a part of the developer’s life, and it’s practically inevitable your app will contain them. But while you’re bound to have glitches in your app, it’s vital you’ve got a method in place to solve them. As the inevitable will happen, be ready to debug your app and also have a plan for those cases when you cannot directly debug with the real device. Learn how to properly obtain logs from your customers’ devices to analyze and fix the bugs.

And of course, crashes will happen in your app, so a crash reporting tool is a must to put in your app. These tools provide invaluable data to iOS developers.

Once you have everything ready on your side, you also need to make sure you complaint with Apple store review guidelines otherwise your app might get rejected in the review process. Pay special attention to new changes Apple introduce over time, for example be sure you fill all the requirements related to your app privacy.