Technical Skills You Need to Become a Pro iOS Dev
21 Sep 2023
One common problem with learning iOS development is that it’s hard to recognize what to learn and what you don’t need to learn, especially if you’re just starting out. This is why in this blog, we’ve outlined the skills you need to have to call yourself a professional iOS Developer. We’ve categorized these skills into beginner, intermediate, and advanced for better clarity.
For this article’s context, we refer to a professional iOS developer as someone who works with a team in a professional setting or workplace. As such, the technical skills you’ll see are different compared to an indie developer. Although this may not always be the case and you could be hired as the only iOS developer in a company, we would always recommend pursuing a company that lets you collaborate with other iOS developers to maximize your growth, especially if it’ll be your first job.
Basic Skills You Need
Xcode is the official integrated development environment (IDE) for iOS app development, providing tools and resources for designing, coding, testing, and debugging iOS applications. It streamlines the development process, offers access to Apple’s extensive libraries and frameworks, and ensures compatibility with iOS devices, making it a fundamental tool for building high-quality iOS apps.
Learning how to use Xcode is not only essential for iOS developers but it would make anyone developing apps for the Apple ecosystem productive as well. As of this writing, the latest Xcode is Xcode 15 and you need a Mac with macOS Ventura 13.5 to install it.
Learn how to use Xcode: https://learn.codewithchris.com/courses/xcode
Download Xcode here: https://developer.apple.com/xcode/resources/
Writing Swift code
Swift is the primary programming language for iOS app development, offering a robust and modern syntax that enhances productivity and performance. Proficiency in Swift enables developers to create efficient, reliable, and user-friendly iOS applications, aligning with industry best practices and Apple’s ecosystem.
The majority of the apps in the App Store are now written in Swift. Swift has matured over the years since 2014, all thanks to the active developer community, and the language continues to evolve for the better. As of this writing, the latest version of Swift is Swift 5.9, which comes pre-installed with Xcode 15.
To get started with learning Swift, we recommend going through the “Swift Tour” here.
Building user interfaces with SwiftUI
Learning how to build user interfaces is vital in becoming an iOS developer because user experience is a cornerstone of app success, and developers need to create intuitive, visually appealing interfaces to engage and retain users. Mastery in interface design using tools allows developers to craft user-friendly, aesthetically pleasing iOS apps that meet Apple’s design guidelines and user expectations.
When building user interfaces, you generally have these options for what approach you can use:
- SwiftUI (recommended) – SwiftUI is a declarative framework that Apple released in 2019. Like Swift, it has continually evolved over the years, and Apple continues to improve it since they want SwiftUI to be the technology building the future of apps in the Apple ecosystem.
- Interface Builder (UIKit) – Interface Builder is the user interface in Xcode that allows developers to create the app’s user interface. Learning how to use the interface builder requires patience as you’ll need to learn how to use different inspectors, the UIKit view library, and the layout constraints system.
- Programmatic UIKit – In this approach, the user interface is built without any use of the Interface Builder. This approach is ideal for apps built by large teams, but the downside is that the code is hard to visualize, and fixing things would require more time and effort.
If you’re someone new, we recommend learning SwiftUI first. Apple’s been clear that SwiftUI is the direction they want the ecosystem to move forward with, but if you want to become a professional iOS developer, you will still need to learn UIKit later in your career.
Also watch: How to Make an App in 8 Days
Debugging (or troubleshooting) code is a critical skill because it helps identify and fix errors and issues in applications, ensuring that the software functions correctly and provides a positive user experience. Effective debugging skills save time and effort in the development process, resulting in more reliable and stable iOS apps.
Before you can debug code, you need to first learn the first three skills highlighted above:
- Using Xcode
If you have the knowledge of how to read and write code, debugging code becomes intrinsically easier.
Also watch: Xcode Debugging Demo
Intermediate Skills You Need
iOS Memory Management
Efficient memory management prevents crashing, and it is an essential intermediate skill to learn. If you’re looking for a job as an iOS developer, you’ll find out that job interviews always include questions about iOS memory management during technical interviews.
By this stage, you should have a solid understanding of the Swift language, and you should know by now the difference between a value type and a reference type.
To learn memory management, you need to learn about ARC (Automatic Reference Counting) and how iOS manages the memory for reference types.
You should also know strategies and techniques to mitigate memory leaks and know how to diagnose one.
Swift concurrency is essential because it enables efficient utilization of multi-core processors, allowing apps to run smoothly and respond to user interactions without freezing or lagging.
Swift concurrency also helps manage tasks for network requests and background processing, enhancing the performance and responsiveness of iOS applications.
When learning Swift concurrency, you will learn about how threading works in iOS, how work is scheduled in different threads, and what responsibilities each thread has to make your app run smoothly.
iOS Networking with URLSession
Interaction with apps is better if it offers online functionality. You can’t imagine using Facebook or Instagram without an internet connection, so you’ll want to learn how to write apps that interface with the network.
You need to learn how to use URLSession to make network requests to remote APIs and process the JSON response with Codable.
Learn more about about iOS Networking here.
Persisting data locally with Core Data or SwiftData
Knowing how to persist data locally with Core Data is important because it provides a powerful and efficient way to manage and persist data within an app, allowing users to interact with content even when offline and ensuring a seamless user experience. Mastering Core Data or SwiftData allows developers to create robust, data-driven iOS applications that can store, retrieve, and manipulate information effectively, which is fundamental for a wide range of app functionalities.
Also watch: Swift Basics in 15 minutes
Proficiency in using Apple’s frameworks and third-party libraries is vital for iOS developers as it allows them to leverage pre-built tools and functionalities, speeding up development, enhancing app capabilities, and ensuring compatibility with Apple’s ecosystem. Familiarity with these frameworks enables developers to tap into a wealth of resources and create feature-rich iOS applications efficiently.
Apple frameworks are built into Xcode by default, and you can simply import them into your Swift code. But using third-party libraries requires the use of either Swift Package Manager or CocoaPods to easily add these libraries as dependencies to your app project.
The Swift Package Manager (SPM) has been built by Apple, while CocoaPods is a third-party dependency manager built by a community of developers.
Learning how to use dependency managers is an essential intermediate skill, as it helps you or your team develop apps faster by using code developed by the open-source community.
If you’re starting out, we recommend learning Swift Package Manager (SPM) first since it comes built-in with Xcode, and you don’t need to install anything to start using it.
However, you’ll also need to learn how to use CocoaPods later in your career, as a lot of apps (especially old ones) are still using it.
Unit testing ensures the reliability and stability of the code by systematically validating individual units or components. By implementing unit tests, developers can catch and rectify issues early in the development process, reducing the likelihood of bugs and enhancing the maintainability and quality of their iOS applications.
Deployment skills are critical for iOS developers to publish their apps to the App Store or distribute them within organizations. Understanding the deployment process involves code signing, provisioning profiles, and App Store guidelines, enabling developers to make their apps accessible to users, clients, or customers, and ultimately turning their development efforts into real-world applications.
Also read: App Store Optimization
Advanced Skills You Need
Learning software design patterns
It’s beneficial for developers to know software design patterns as it provides a structured approach to solving common development problems. It enhances code readability, maintainability, and collaboration among developers, ensuring that iOS applications are well-organized, scalable, and easier to extend or modify in the future.
Recommended patterns for iOS development:
- Delegation Pattern
- Design Patterns by the Gang of Four (Swift)
- Architectural Patterns: Apple MVC, MVVM (and its variants), VIPER, and CLEAN
It’s important to have a solid understanding of algorithms because they directly impact the efficiency and performance of their applications. Many major apps nowadays use algorithms because they lead to faster execution times and reduced resource consumption, resulting in smoother user experiences and the ability to handle complex tasks or data processing effectively.
Big O Notation
On the topic of algorithms, we also recommend understanding Big O Notation as it serves as a standardized notation system that allows developers and engineers to assess and compare the efficiency of different algorithms. Familiarity with Big O Notation will enable you to make informed decisions when designing and optimizing software, ultimately leading to more efficient and scalable applications.
Xcode Instruments offers precise performance analysis and debugging capabilities for iOS and macOS applications. It helps identify and rectify performance bottlenecks and memory issues, ensuring that software runs smoothly and efficiently to deliver a superior user experience.
All of these skills are related to writing great code instead of code that just works.
These are roughly what you need to know as an iOS professional. But, even if you know all of these, you will be learning lessons, techniques, and new skills on the job every day. As a developer, the learning never stops as different projects will require different solutions.
Now that you have an idea about the skills you need to have, the next step is to start learning from scratch.
Start learning with CodeWithChris today and master the basics of iOS Development. Click here to learn more.