SwiftUI vs UIKit: The best choice for iOS in 2025

Which framework is right for an iOS app development project?

This blog post will discuss the differences between SwiftUI and UIKit and which frameworks are preferable for performance, flexibility, and ease of use. The right framework is vital for flawless and high-performing app building, given that most apps exist in the App Store and have 1.46 billion iPhone users worldwide.

When comparing the benefits and drawbacks of every framework, SwiftUI stands out for its more contemporary critical syntax and seamless compatibility with the latest Apple technology. On the other hand, UIKit will still be a good option because of its longer evolution and powerful performance, especially in handling large-scale, complex legacy systems. 

By the end of this post, you will have good information about SwiftUI vs Uikit’s performance and more aspects. You will also know when and when not to use these frameworks, which will help you decide on your next mobile application development project.

Understanding SwiftUI and UIKit

What is SwiftUI?

SwiftUI is Apple’s framework for creating user interfaces. It launched in 2019 in parallel to Swift, the language. SwiftUI is built upon a declarative syntax that lets developers describe interfaces while the framework optimizes for rendering. 

Some features include inline previews, which provide a last look at the layout before making further changes, responsiveness aspects for different devices, several ways and alternatives regarding the native controls, and necessary component reuse. SwiftUI still looks more natural and seamless compared to older frameworks, such as UIKit, which is more suitable for developers working on Apple platforms.

What is UIKit?

Since the first launch of the iPhone in 2007, UIKit has been a base kit for building iOS and macOS, watchOS and tvOS applications. Compared to SwiftUI’s oriented approach, UIKit provides an imperative way of building user interfaces and manipulating UI elements.  

UIKit is quite mature, well documented, and has a vast community. It indicates that to this day, Apple still supports UIKit and the possibility of transitioning to it from new frameworks like SwiftUI.However, it offers many possibilities for customizations and API to design and implement user interfaces, which makes the framework more popular despite the appearance of SwiftUI.

What Are the Benefits of Using Swiftui?

1) Real-Time UI Preview while Coding

With SwiftUI, Xcode’s Integrated Development Environment (IDE) displays real-time interface previews. Developers can preview changes directly with the canvas feature, located on the right side of the editor. This aspect facilitates the design and visualization of the application across various platforms and modes. You can also choose a device for light or dark mode. Any changes you make to the UI afterwards will also be displayed on the canvas.

2) Facilitates Cross-Platform Development

Using a single code base, SwiftUI allows developers to develop iOS, macOS, TVOS, watchOS, and vision applications. It is a UI layer that supports various Apple platforms, including iOS, TVOS, watchOS, macOS, and even visionOS.

3) Interoperability with Existing UI Frameworks

SwiftUI integrates perfectly with UIKit for iOS and AppKit for macOS. It is possible to include SwiftUI elements into the already developed applications or replace original UIKit/AppKit components with SwiftUI-based interfaces while reusing as many existing code blocks as possible.

4) Easy Maintenance:

Since SwiftUI defines UI components in code, there is no need to maintain the application with extensive Storyboard files. This approach ensures that editing, updating, and reusing views is easy and can be accomplished quickly.

What Are the Benefits of Using Uikit?

1) Mature Ecosystem:

UIKit can offer a stable code context that has been tried and developed over time. This maturity provides solidity and dependability to the development process and thorough testing and enhancements implemented by Apple software and international developers. 

The main factor makes many tools, resources, and documentation to help developers create scalable iOS applications.

2) Extensive Customization:

It is also important to mention that UIKit provides a great number of tools to customize the interface to the proposed guidelines so that developers gain the ability to make necessary changes. Being a rich and comprehensive library, one can change the application’s stylistic and functional UI characteristics to meet customer requirements.

This flexibility facilitates the creation of interfaces that align with a specific interface brand, design standards, and visions.

3) Wide Adoption:

This means developers can access various resources, tutorials, and experiences.UIKit is the native framework Apple uses for iOS applications within the iOS development community.  A large, active community can share experience and knowledge, permanently developing and improving the ecosystem and offering developers higher support.

What are the Drawbacks of Using SwiftUI?

1) Limited Compatibility:

SwiftUI, introduced with iOS 13, is incompatible with earlier versions of iOS. Thus, developers experience hardships if they wish to deploy their apps to devices using prior iOS versions. Individuals planning to have their applications support multiple iOS versions must use the UIKit together with SwiftUI or can use the UIKit solely.

2) Learning Curve:

It may be difficult for developers using UIKit to shift to SwiftUI. SwiftUI has a cleaner UI design concept than UIKit, but its concepts and approach to work may take some time to understand.

3) Lack of Maturity:

Like any other relatively new technology, SwiftUI has its drawbacks of a new framework inapplicable that it probably has more limitations, issues, or fewer features than UIKit.

What Are the Drawbacks of Using Uikit?

1) Extensive Code Writing:

UIKit involves more extensive writing of basic codes than SwiftUI and is thus likely to result in code expansion, which will complicate the project, especially in developing complex UIs.

2) Complexity:

UIKit defines the way of designing interfaces, taking an imperative position. The UI developer is required to declare all the single activities of construction and modifications. It can make the code more layered and confusing than following the application’s logic compared to SwiftUI.

3) Lack of live preview:

When dealing with UI elements, developers need to run the application, at least the simulator or device, to see the changes made, which takes time. Unlike SwiftUI, UIKit does not offer live preview features, whereby designers can see the progress as they use the interface.

Major Differences between SwiftUI and UIKit

What Does the Programming Style Look Like, Declarative or Imperative?

A) Declarative vs Imperative Programming Style

1) UIKit:

In UIKit, programming methodology is fundamentally imperative. This means that developers must document each stage and aspect of how the interface should be built and modified. The conventions require the developers to be specific about what needs to be done and how to do it to get the particular result of the UI changes.

2) SwiftUI:

In contrast, SwiftUI applies the declarative approach to structuring the code. Here, developers specify the desired end state as to how a particular UI should be rendered, say, based on the current app state and data. The framework then calculates how the UI should be modified to align with the description in the statement.

As a result, code is less replicative and more understandable as developers write more what they desire instead of how it should be done.

B) How Does Cross-Platform Compatibility Compare?

1) UIKit:

UIKit mainly focuses on developing applications for the iOS operating system only. Although some components of UIKit may be applied to other Apple platforms, such as macOS, tvOS, and watchOS, UIKit is not compatible with non-Apple systems by default.

2) SwiftUI:

SwiftUI is built with cross-compilation functionality in mind. A unified reference code enables developers to build graphical interfaces that will be operational across all Apple platforms, including iOS, macOS, watchOS, and TVOS. This will enable the developers to create apps compatible with multiple devices.

C) How Does the Learning Curve Differ?

1) UIKit:

However, as mentioned earlier, it can be difficult for new developers to learn UIKit due to its imperative approach and nested classes and views. Ideally, high-level concepts such as view controllers, delegates, and data sources are vital for any developer when designing interfaces in the iOS environment.

2) SwiftUI:

The above tutorial shows that SwiftUI is relatively easier to learn than UIKit, especially for anyone or new. The declarative syntax makes creating application UIs easier and abstracts over many low-level APIs in UIKit. Another feature that makes SwiftUI preferable is a live preview that allows viewing the changes in real-time and helps developers learn it and practice creating interfaces. Swift app development enables one to develop good responsive and feature-rich applications for Apple devices in less time.

Performance Comparison

Here, this section properly explains SwiftUI vs UIKit performance.

SwiftUI and UIKit are two user interface frameworks for developing applications for iOS devices. First, SwiftUI is more modern in terms of the language, state, and logical approaches used, and its code is more laconic than UIView, which can have some advantages in terms of performance in some cases. On the other hand, UIKit is an imperative language freshers might find slightly difficult to work on. Still, it provides good control over the UI components and is good for complicated projects.

It has been ascertained that UIKit traditionally performs better than SwiftUI regarding key performance indicators; in the case of the productivity rate for average UI elements, UIKit stands significantly ahead. This advantage is particularly important for solutions that demand the maximal usage of resources and time to execute some action. 

However, UIKit provides more up-to-date characteristics and ease of working compared to SwiftUI, at least for now, its efficiency indicators are higher.

Swiftui vs Uikit: Which Is Better?

When is SwiftUI most suitable?

• Directly useful for new applications or when aiming at the newer versions of iOS.
• Most ideal for creating feasibility proofs and muse over formative proofs.
• Very useful for creating sophisticated, aesthetic, and graphic user interfaces.
• Ensures it has a declarative syntax, making it easier to develop the UI.
• Provides users with real-time visualization to allow for editing as the design is made.

When is UIKit most suitable?

• Initial projects or projects that need to run on older iOS versions
• Applications that have to work with complicated and highly specific graphical interfaces
• If more significant customization and fine-tuning of specific UI elements are required
• More suitable for developers already using UIKit and clearly understand how it is built.
• It is more flexible and provides more control over the UI than SwiftUI.

Difference Between SwiftUI vs UIkit

Here is a comparison table that gives you proper information about swiftui vs uikit comparison.

Conclusion-   SwiftUI vs UIKit: Which is the best framework?

You can answer the question from the above discussion: SwiftUI vs UIKit: The best choice for iOS.So, when choosing SwiftUI over UIKit or vice versa and when creating an iOS app, there are some factors to consider:

• The experience of developers, whether the team has expertise in SwiftUI, UIKit, or both frameworks.
• The specifics of the project.
• The timelines.
• The likely need for an app scaling.
• The potential for long-term maintenance of the created application.

When discussing SwiftUI vs UIKit example scenarios, for new projects that prioritize compatibility with several platforms or speed of prototyping, SwiftUI’s approach and the latest tools might be extremely beneficial. 

Yet, for more complex projects requiring a certain level of customization or integration with existing UIKit-based projects, it will still be more reasonable to continue using UIKit.Consider working with a specialized swift app development company for swift app development.
Contact us at iCoderz to hire the best Swift app developers for your projects.

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