Articles about Swift and iOS development

Testing callbacks with confirmations in Swift Testing

Learn how to verify that callback-based events occur the expected number of times.

Parameterized tests and test organization with Swift Testing

Learn how to cover multiple inputs with parameterized tests and organize a growing Swift Testing test suite.

Building responsive and reliable search in SwiftUI

Learn how to debounce search input, cancel obsolete requests and prevent stale results using Swift concurrency.

Getting started with Live Activities in SwiftUI

Build a public transport journey tracker for the Lock Screen and Dynamic Island with ActivityKit.

Managing toolbar visibility and overflow in SwiftUI

Learn how to prioritize, pin and move SwiftUI toolbar actions into an overflow menu.

Presenting alerts and confirmation dialogs from identifiable data in SwiftUI

Learn how to present alerts and confirmation dialogs using optional identifiable items instead of Boolean state.

Adding swipe actions to any SwiftUI scroll view

Learn how to use swipe actions outside of List in SwiftUI.

Managing focus in SwiftUI with FocusState

Learn how to observe, move, and remove focus in SwiftUI views.

Building a reusable API client with URLSession in Swift

Learn how to structure networking code with URLSession, async/await, response validation, and JSON decoding.

Building widgets with WidgetKit and SwiftUI

Learn how to create widgets for an iOS application with WidgetKit and SwiftUI.

Keeping SwiftData behind a boundary

Learn how to keep SwiftData out of SwiftUI views.

Understanding Sendable in Swift

Learn what Sendable means in Swift concurrency and how it helps prevent data races.

Getting started with Apple's Foundation Models framework

Learn what Apple's Foundation Models framework is, how it works, and when to use it.

Async cleanup with defer in Swift

Learn how to perform asynchronous cleanup operations using Swift's async defer support.

Registering for push notifications in SwiftUI

Learn how to request notification permissions and register for remote notifications in a SwiftUI app.

Working with the Keychain in iOS

Learn how to securely store sensitive data using Apple’s Keychain Services API.

Understanding basic animations in SwiftUI

Learn how to animate state changes in SwiftUI views.

How to present a local HTML file in SwiftUI

Learn how to show a locally stored HTML file with WebView and WKWebView

How to implement pagination with SwiftUI's List view

Learn how to implement infinite scrolling with SwiftUI.

Building a draggable bottom sheet in SwiftUI

Learn how to build a draggable bottom sheet using presentation detents.

How to test in-app purchases locally using StoreKit

A practical guide to simulating in-app purchases and subscriptions in Xcode.

Working with files and directories in iOS

Understanding the app sandbox and how to access system directories.

Migrating to String Catalogs in iOS

Learn about migration strategies from Localizable.strings to .xcstrings.

Working with String Catalogs in iOS projects

Practical tips, limitations, and best practices for localization with .xcstrings files.

How to use custom names for Swift properties when decoding JSON data

Learn how to map JSON keys to differently named Swift properties using CodingKeys.

Implementing Passkeys in iOS with AuthenticationServices

A practical introduction to passwordless authentication using passkeys on iOS.

How to build a simple CLI tool using Swift

Create small automation tools with Swift and ArgumentParser.

How to use SwiftUI Coordinators to communicate with UIKit

Bridging UIKit delegates and events back into SwiftUI.

Migrating to the Observation framework in SwiftUI

Learn how to use SwiftUI's @Observable macro.

A visual cheat sheet of Combine operators

A diagram-based reference for common Combine publisher operators.

How to use String Catalogs for pluralization in Swift

Learn how to handle plural forms correctly with String Catalogs.

Memory management in Combine

Understand how retain cycles appear and when they turn into memory leaks in Combine.

Storing Swift structs in UserDefaults

Why Codable works but often isn't the best choice.

Understanding date decoding strategies when working with JSON in Swift

Learn how Swift decodes dates and how to handle real-world formats.

Understanding SwiftUI's Grid container

Learn how to arrange views in a two-dimensional layout.

Adding text input actions to iOS push and local notifications

Learn how to let users reply directly inside a notification.

How to avoid retain cycles when working with tasks in Swift

Understanding memory management in Swift concurrency.

Bridging completion handlers to Swift's async/await

Learn how to adapt completion-based APIs to Swift's concurrency model using continuations.

Transforming AsyncStream with Swift Async Algorithms

Bringing Combine-like operators to Swift concurrency.

Understanding Task and Task.detached in Swift concurrency

Learn the what the differences are between Task and Task.detached in Swift.

Understanding task cancellation and lifetimes in Swift concurrency

Learn how structured and unstructured tasks behave in Swift's concurrency system.

Comparing Combine's subjects with AsyncStream in Swift

Exploring how Swift concurrency can handle event streams compared with Combine.

When SwiftUI automatically applies the glass look and when it doesn’t

Understanding where SwiftUI decides to use the new glass styles automatically.

How to add custom actions to iOS push and local notifications in SwiftUI

Learn how to let users respond to notifications without opening the app.

Cancelling async tasks in SwiftUI

Learn how to cancel async work in SwiftUI with automatic and manual approaches.

How to manage app lifecycle events in SwiftUI

Discover SwiftUI’s scenePhase environment and how to respond to app state changes.

Understanding SwiftUI's liquid glass button styles

Learn about different ways to apply Apple's glass style.

Switching Swift Package Manager dependencies between versioned and local development

Quick tip on switching a self-developed Swift package from a versioned dependency to a local path for development.

How to use async/await in synchronous Swift code with tasks

Learn how to use tasks to call async/await methods from synchronous code.

My new book on architecture & design patterns for iOS

I finally finished my new book on building scalable and maintainable apps with Swift and SwiftUI.

How to create a custom reusable toolbar in SwiftUI

Learn how to abstract and reuse a SwiftUI toolbar across multiple screens.

How to use the @available attribute in Swift

Learn to make Swift code only available for certain language versions or platforms.

Using defer in Swift to manage state cleanup

Learn how to use defer to handle cleanup logic in async functions.

Understanding toolbars in SwiftUI

Learn how to add toolbar items in SwiftUI views across various placements like navigation bars, bottom bars and more.

Learn to build adaptive layouts with SwiftUI's ViewThatFits container.

Understand how SwiftUI's ViewThatFits container works.

Scheduling notifications with time, calendar, and location triggers in iOS

Learn how to schedule local notifications using different trigger types with the UserNotifications framework.

Working with Xcode configuration files

Learn how to manage different iOS build environments with .xcconfig files.

Creating and managing multiple app environments in Xcode

Learn how to add and configure debug, staging, and release environments in your iOS app using Xcode.

Understanding Xcode targets, schemes and build configurations

Learn the foundational concepts of Xcode build configuration and how targets, schemes, and configurations work together.

Bridging interfaces with the Adapter pattern in Swift

Learn how to use the Adapter pattern to integrate third-party APIs or legacy code.

How to persist navigation state in SwiftUI

Learn how to save and restore NavigationPath to maintain user context across app launches.

Using NavigationPath with TabView in SwiftUI

Learn how to integrate NavigationPath with TabView in SwiftUI to manage independent navigation flows.

Testing remote iOS push notifications in a simulator with simctl

Learn how to use the command-line tool simctl to simulate remote notifications in iOS.

Building a dependency injection framework

Learn how to create a lightweight dependency injection container in Swift

Public-key cryptography with CryptoKit for iOS

Learn how to use CryptoKit to increase security in iOS applications.

Understanding existentials and primary associated types in Swift

How existentials and primary associated types enhance flexibility in protocols.

Understanding structural identity in SwiftUI

Learn how SwiftUI optimizes UI updates.

Understanding the Bindable property wrapper in SwiftUI

Learn how and when to use @Bindable in SwiftUI.

Quick guide on home screen quick actions for SwiftUI

Learn how to provide users with direct access to app functionality from the home screen.

How to use SceneDelegate in SwiftUI

Learn how to integrate SceneDelegate with a SwiftUI-based application.

Implementing Face ID authentication in SwiftUI

Learn how to add biometric authentication with passcode fallback to secure your app.

SF Symbols guide for SwiftUI and UIKit

Learn how to use SF Symbols for consistent, scalable icons in iOS.

Customizing the appearance of the NavigationStack title in SwiftUI

Learn how to create a custom navigation bar title view in SwiftUI using NavigationStack.

How to use cryptographic hash functions in CryptoKit for iOS security

Learn how to implement cryptographic hash functions in Swift.

Preparing for a technical iOS job interview with questions and answers in 2025 - book preview

An updated book version with a new chapter on Architecture & Design Patterns is now available.

Understanding opaque types and protocols with associatedtype in Swift

Learn how to leverage the some keyword for working with protocols with associated types.

Getting started with UI Testing for SwiftUI

Learn how to create user interface tests with the XCTest framework.

Creating a particles snow effect with SpriteKit and SwiftUI

Learn how to create a realistic snow particle effect in SwiftUI using SpriteKit’s particle emitter.

How to unit test async/await functions in Swift

Learn how to write unit tests for async/await functions.

Understanding opaque types in Swift

Explore opaque types in Swift for building flexible and type-safe abstractions.

How to use a Connectable publisher in Combine

Learn how to prevent data loss by using Combine's ConnectablePublisher.

Dynamic colors in SwiftUI

Learn to use the asset catalog or the programmatic approach to define dynamic colors in SwiftUI.

Understanding actors in Swift

Learn how to use Swift actors to prevent data races when working with concurrency.

Extending optionals in Swift

Quick tip on how to extend an optional in Swift.

Getting started with async/await in Swift

Learn how use async/await for asynchronous programming.

Understanding Substring and String indices in Swift

Learn how to use Swift's String type and its companions Character, Index and Substring.

How to set up and use Core Data with SwiftUI

Learn the basics for using the Core Data framework with SwiftUI in iOS.

Swift optionals cheat sheet

Get an overview on Swift optionals, including optional binding, forced unwrapping, implicit optionals, nil coalescing operator and more.

How to call async/await functions concurrently in Swift

Learn how to call async/await functions in parallel with tasks.

Understanding the @FetchRequest property wrapper in SwiftUI

Learn how to request data from the Core Data store in a SwiftUI view.

Understanding the @Environment property wrapper in SwiftUI

Learn different scenarios for using the @Environment property wrapper.

How to delay server requests for user's search query with SwiftUI and Combine

Learn how to debounce on a practical example.

Backpressure in Combine

Understand the concept behind backpressure and how to apply it in Combine.

Developer guide on Swift Testing for iOS

Learn how use Swift Testing to write automated tests.

Objective-C basics for Swift developers

Quick reference of key Objective-C concepts.

Combine essentials in Swift - a quick guide

Learn basic Combine concepts and terms.

How to combine SwiftUI and UIKit views in iOS

Learn how to bridge SwiftUI and UIKit views.

How to solve problems with bitwise operators in Swift

Learn to use the power of bitwise operations and option sets in iOS.

GraphQL essentials for iOS development

Understand the concept behind GraphQL in context of iOS development.

Quick tip on adding child view controllers programmatically in UIKit

A Swift extension for programmatically adding child view controllers.

Introduction to Combine for iOS developers with RxSwift experience

How to start using Combine for reactive programming

How to avoid using AnyView in SwiftUI

By using alternatives such as the @ViewBuilder attribute, Group type or generics.

How to use Swift's logging API

Learn how to log events and errors in your iOS app with Swift's logging API.

How to support dark mode in SwiftUI programmatically

Learn how to improve type safety when working with semantic colors.

Safe array subscription in Swift

An extension to access array elements with conditional binding

How to use TipKit to create tool tips in SwiftUI

Learn how to show feature hints as a popover to the user by using TipKit.

How to delay an animation in SwiftUI

Learn how to wait for a certain amount of time before starting a SwiftUI animation.

How to define one-to-many relationships in SwiftData

Learn to use SwiftData's @Relationship macro.

Getting started with Apollo iOS for GraphQL in Swift

Learn how to integrate GraphQL into a Swift application using Apollo iOS.

Get started with auto‑renewable subscriptions for iOS

Learn how to implement in-app purchase subscriptions with StoreKit and SwiftUI.

Introduction to Kotlin for Swift developers - protocols, extensions & generics

Learn how protocols, extensions and generics in Kotlin work from a Swift developer's point of view.

How to store images in SwiftData

Learn how to efficiently store larger amounts of data in SwiftData.

How to migrate to a new schema with SwiftData in iOS

Learn how to create a migration plan in SwiftData.

How to implemet a free trial period for StoreKit 2 subscriptions in iOS

Learn how to implement StoreKit 2 introductory offers.

How to get a SwiftData model container and context in SwiftUI

Learn how to setup a SwiftData container and context directly in SwiftUI.

Quick developer guide on SwiftData for iOS

Get an overview on Apple's SwiftData framework.

How to restore in-app purchases with StoreKit 2 for iOS

Learn how to restore in-app purchases proactively and with a restore purchases button.

Get started with StoreKit 2 for iOS

Learn how to implement in-app purchases and subscriptions with StoreKit 2.

Introduction to Kotlin for Swift developers - classes, structs & enums

Learn how classes, structs and enums work in Kotlin from a Swift developer's point of view.

How to manually subscribe to changes of SwiftUI's @Observable objects

Learn how to use the withObservationTracking method of the Observation framework.

Introduction to Kotlin for Swift developers - variables, functions & control flow

Learn the main concepts of Kotlin from a Swift developer's point of view.

The difference between @StateObject and @ObservedObject in SwiftUI

Learn how to correctly use the property wrappers StateObject and ObservedObject.

Beginner's guide on Flutter for iOS developers

Learn the main concepts of Flutter from a native iOS developer's point of view.

Quick tip on how to split text into words with the Natural Language framework in Swift.

Learn how the tokenizer of the Natural Language framework works.

How to find synonyms with the Natural Language framework for iOS

Learn how to find similar words or sentences in Swift.

How to map a SwiftUI state to a binding of a different type

Learn how to create custom SwiftUI bindings.

How to identify parts of speech and names in a text with Swift

Learn to use the linguistic tagging possibilities provided by the Natural Language framework in iOS.

How to detect the language of a text with the Natural Language framework in Swift

Learn to use the language recognizer of the Natural Language framework.

Cheatsheet for the JSON payload of an iOS push notification

Learn the structure and configuration possibilities of a remote push notification.

How to scan QR codes with VisionKit for iOS

Learn how to use the DataScannerViewController to scan QR codes.

Get started with Create ML to train a machine learning model in iOS

Learn how to use Create ML to create machinge learning models.

How to change JSON keys by using Swift's CodingKey protocol

Learn how to map JSON data to a different structure in Swift.

Get started with NSPredicate to filter NSFetchRequest in Core Data

Get a quick overview on how to use predicates to filter fetch request results.

Developer guide on machine learning for iOS with Core ML

Learn basic machine learning concepts and how to use machine learning in iOS.

Quick tip on how to unit test Swift optionals with XCTUnwrap

Learn how to shorten if let and guard statements when unit testing.

How to import Objective-C types as optionals or non-optionals into Swift

Learn how to use nullability declarations and macros.

Understanding different cache policies when working with URLRequest in Swift

Learn how to manage cache when sending HTTP requests in your iOS applications.

iOS developer guide on the main aspects of Core Data

Understand the main concepts of the Core Data framework.

How to manage view lifecycle events in SwiftUI

Discover SwiftUI's view lifecycle events onAppear, onDisappear, task, and task(id:).

Building configurable widgets with WidgetKit and SwiftUI

Learn how to let users customize a WidgetKit widget with App Intents.

How to bridge async/await functions to Combine's Future type in Swift

Learn how to call async/await code within Combine based APIs.

Customizing buttons in SwiftUI with the ButtonStyle protocol

Learn how to reuse button styles in SwiftUI.

Customizing the appearance of the NavigationView title in SwiftUI

Learn how to create a custom navigation bar title view in SwiftUI.

Quick guide on local notifications for iOS

Learn how to schedule and handle local notifications using the UserNotifications framework.

Symmetric-key cryptography with CryptoKit for iOS

Using CryptoKit to increase security in iOS applications.