Swift vs Objective-C: Which One Is Better For iOS Development?

Most likely, you've asked yourself, "Should we use Swift or Objective-C?" when you're making an iOS app.  It's a popular question among people who work with iOS development.

Two key languages used in developing iOS apps are Swift and Objective-C.  Swift is the most recent version, which was developed by Apple to simplify and enhance the process of app development. Originally around for much longer, Objective-C still runs many current programs, particularly older or enterprise-level ones.

Choosing one of these two languages can affect your project's speed, maintenance, teamwork, and future changes as well.  To assist you choose the correct language for your project or team, this post will thoroughly compare both languages with code examples, explanations of how each one works, and practical advice on when to use one.

Evolution of Swift and Objective-C

Many years ago, if you wanted to build an iOS app, there was only one option, Objective-C. It worked well for a long time, but as apps became more complex, some problems started to show. Developers started running into problems with code safety, memory bugs, and hard-to-understand crashes. These issues made development slower and harder to maintain, especially for large teams or long-term projects.

Apple saw these problems and decided to build something better. They introduced Swift, a brand new language built from scratch to make iOS coding easier and safer. Swift removed the confusing parts of Objective-C and replaced them with smart, modern features. Developers no longer had to worry about bugs or unexpected nil values.

Although, at first, many developers were afraid to use it in real projects due to its instability in coding. However, Apple didn’t stop improving it. They kept making it better, and more stable. Today, Swift is popularly used in every new iOS app. Many older apps are also slowly being updated. Apple is moving forward with Swift at the center of its platform.

What is Swift? 

Swift is a new iOS development language made by Apple. It is used to make apps that work on Apple's systems, including iOS, macOS, watchOS, and tvOS. Introduced in 2014 to replace Objective-C, Swift allows for simplified, safer, and faster app development.

In writing and reading code, Swift is simpler than Objective-C. This programming language catches typical mistakes while you develop and runs apps faster with a strong compile. Swift has grown over the years to be the primary choice for iOS developers, particularly with modern development tools like SwiftUI designed to fit it.

Advantages of Swift Compared to Objective-C:

• Easier to Read: Swift's straightforward and clean language makes the code easier to follow even for beginners.
• Catch Mistakes: It looks for mistakes when you code to avoid problems before the app even runs.
• Less Code: Fewer lines needed for developers to save time and ease program maintenance.
• Modern Features: Swift offers features to streamline development including asynchronous code, closures, and options.
• Optimized for Newer Tools: Swift works perfectly with SwiftUI and Combine which are engineered for recent apps.
• More Updates: Apple is prioritizing Swift with new features and refinements.

What is Objective-C? 

Objective-C is an older iOS programming language. It was created in the 1980s and was the main language for iOS and macOS development before Swift joined this industry. Many large and long-running apps are still written in Objective-C because Apple continues to support it.

Unlike Swift, Objective-C is built on top of the C language. This gives it a lot of flexibility, but it also makes the syntax more difficult to read. Objective-C uses dynamic typing and message-passing, which can be powerful but also harder to manage in large codebases. Even though it’s no longer the first choice for modern apps, it is still important for maintaining older apps and working with some mobile frameworks.

Advantages of Objective-C Compared to Swift:

• Very Stable: Objective-C has been used for years, and code written a long time ago still works well today.
• Flexible at Runtime: It lets developers do or update more things while the app is running, which can be helpful in some advanced cases.
• Works Well with C/C++: If your app uses older C or C++ code, Objective-C makes it easier to connect everything.
• Good for Older Projects: Many older libraries and frameworks used in former apps were made for Objective-C, so this language fits better in some situations.
• Trusted by Experienced Teams: Developers who’ve used Objective-C for years are comfortable with its style and features.

Swift vs Objective-C: Key Differences

Swift and Objective-C take different approaches to iOS development. This section breaks down how they compare in key areas like syntax, performance, memory, and overall developer experience.

Syntax 

Swift was designed to be simple and clean, while Objective-C follows an older, more complex style. You can see the difference right away, even in something as basic as a greeting message returning function as below.

Swift code:

Objective-C code:

As you can see, Swift's code is straightforward and short. The function uses natural-looking syntax and the string interpolation seems logical. In Objective-C, the method has a longer format with brackets, colons, and a format string. It still works well, but it takes more time to write and understand, especially for people new to iOS development.

This is one of the main reasons why Swift is now more popular for new projects. It helps developers write code faster, with fewer mistakes that are hard to catch.

Performance 

In terms of performance, Swift generally performs better than Objective-C, especially in modern app development. Swift, a statically typed language, compiles directly to optimized machine code using the LLVM compiler. This allows Swift to benefit from compile-time optimizations such as inlining, dead code elimination, and memory access improvements, which can result in faster execution.

Objective-C relies on a dynamic runtime. Before Swift's static dispatch, Objective-C method calls were handled by passing messages at runtime, which adds flexibility in some extra work. This flexibility is useful in some advanced scenarios but can reduce performance in apps with heavy or repeated method calls.

Memory Management 

Swift and Objective-C both use Automatic Reference Counting (ARC) to manage memory, which keeps track of how many times a piece of data is being used. When that data is no longer needed, ARC automatically clears it from memory. 

The main difference is that Swift makes memory handling safer. It uses features like options and strict typing to help developers avoid common problems like memory leaks or retain cycles. In Objective-C, developers have more control, but that also means it is easier to make mistakes if they're not careful. For most developers, Swift makes it easier to write memory-safe code without having to spend effort and time to fix code problems.

Tooling

Recently, both languages can work well with Xcode, but Swift has gotten more updates and support from Apple. It supports useful features like code suggestions, real-time error checks, and quick previews when using SwiftUI. You can also use Swift Playgrounds to test small ideas without building a full app. These tools help speed up development and make the coding process smoother.

Objective-C still supports the same debugger, interface builder, and performance tools in Xcode. However, some of the newer features like SwiftUI, Combine, or Playgrounds are not made for this language. So while both languages work in Apple’s tools, Swift gives a better experience, especially when using the latest frameworks.

Interoperability 

One of the helpful things about iOS development is that Swift and Objective-C can work together on the same project. This is especially important for apps that were originally written in Objective-C but are now adding new features in Swift. Apple made sure these two languages can talk to each other, so developers don’t need to rewrite everything when switching to Swift.

Swift can import Objective-C code from a bridging header. This lets Swift use Objective-C classes, methods, and properties almost like they were written in Swift. Meanwhile, using Swift code in Objective-C requires a few more steps such as Swift must be highlighted with @objc. Furthermore, some Swift features also don't operate on Objective-C at all.

Community

Swift has a fast-growing community. Since it’s open source, many developers contribute to its development and share useful tools, libraries, and tutorials online. There are plenty of resources for learning Swift, from beginner guides to advanced courses. You’ll also find lots of Swift’s Q&As on forums like Stack Overflow and Reddit.

Objective-C has been used for a long time, so it has a large base of knowledge and documentation. Many older libraries and code examples are written in Objective-C, which can still be helpful. However, most new learning materials and community discussions today focus on Swift, as it’s now the main language used in iOS development.

Learning Curve

Most developers find Swift easier to work with, especially if they’re just starting. The code looks clean and the rules make sense, so developers can pick it up faster. Swift also points out errors as you code, which helps beginners understand what’s going wrong and how to fix it right away.

Objective-C is more complicated. The way the code is written takes time to get used to. Some parts like brackets, method naming, and message passing can be confusing at first. It’s better suited for developers who already have experience with older Apple systems or who need to work with legacy codebases.

Stability 

Swift has come a long way since it was first released. In the beginning, the language changed often, and those changes sometimes broke older code. This made some developers cautious about using it in big or long-term projects. But over the past few years, Swift has become much more stable. Apple now focuses on keeping the language consistent and provides tools to help update older Swift code smoothly.

Objective-C, on the other hand, has always been very stable. It’s been used for decades, and many apps built years ago still run without major issues. The language doesn’t change much, which is helpful for maintaining large, long-running projects.

Safety

Swift was built with safety in mind. It helps catch mistakes while you write code by using features like optionals, strict typing, and built-in error handling. This reduces the chances of crashes or unexpected bugs when the app is running.

Objective-C is more flexible but doesn’t offer the same safety checks. You can write code faster in some cases, but it’s also easier to make small mistakes that cause problems later. In short, Swift is still the better choice to write safer, more stable apps.

Flexibility

Swift is designed to be strict and predictable. It uses static typing and doesn’t support many dynamic features like changing method behavior at runtime. This makes the code safer and easier to understand. But it also means there’s less room for runtime tricks or advanced patterns that some developers might need.

Objective-C, on the other hand, is much more flexible. It allows dynamic typing, method swizzling, and other runtime changes that give developers more control. This can be helpful in certain situations, like building plugins, creating frameworks, or working with older APIs. So while Swift keeps things safe and simple, Objective-C offers more freedom when you need it.

When To Use Swift?

Choosing between Swift and Objective-C depends on what kind of project you’re working on and what your team works well with. Each language fits different needs.

Swift is the best choice for the latest iOS, macOS, watchOS, or tvOS projects. If you're starting from scratch or building a modern app, Swift will help you write cleaner code, avoid common bugs, and work faster. It's also easier for new developers to learn. This language is also a good fit for teams that want to move fast without sacrificing code quality. 

When To Choose Objective-C?

Objective-C is still a good choice when you're working with older apps that were already developed with it. Many long-running iOS and macOS projects have large codebases written in Objective-C. In these cases, it’s more practical to keep using Objective-C, especially if the app is stable and well-tested.

You might also choose Objective-C if you're building features that rely on older Apple frameworks or third-party libraries that haven’t been updated for Swift. Objective-C still works better in some low-level system tasks or when working closely with C or C++ code.

However, in some cases, teams can even use both languages together. Swift can handle new features, while Objective-C stays in place for parts that already work well. This mixed approach helps avoid unnecessary rewrites and keeps the app stable during changes.

Future Outlook of Swift and Objective-C

Swift is the future of iOS development. Apple continues to add new features to Swift and builds its latest tools, such as SwiftUI, Combine, and async/await. Most of the learning materials, sample projects, and WWDC sessions now focus on Swift. New developers entering the Apple ecosystem usually start with Swift because it’s easier to learn and matches Apple’s current direction.

Objective-C is still supported, and Apple hasn’t announced plans to remove it. Many apps still use it, especially in large companies or older systems. However, Objective-C isn’t getting much attention in terms of new features or modern development tools. It’s stable and reliable but slowly becoming a better fit for maintaining legacy code rather than starting new projects.

In other words, if you're building something new, Swift is the safer long-term choice. But for older apps that already run well, Objective-C still performs better.

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Conclusion

Swift and Objective-C both have their strengths. Swift is easier to learn, safer, and works best with all the latest tools. While, Objective-C is still stable, and works well with older apps and lower-level tasks. If your app already uses Objective-C and it is running fine, there may be no need to switch right away.

In the end, the best choice depends on your project. Remember to consider your project type, whether it is a new app development project or maintaining your old app feature, and requirements before deciding on which language is suitable for your app projects.

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