Learn four techniques of unit testing concurrent code in Swift using the XCTest framework: mocking, test before & after, XCTestExpectation, busy assertion.

How is it that 'Optional<AnyObject>' is the same size as 'AnyObject'?

App Store server notifications provide real-time updates on a subscriber’s status, so you can create customized user experiences. The following new notifications are now available in production:

DID_RENEW lets you know when a subscriber successfully auto…

Exploring iOS, SwiftUI & much more.

Learn how to deal with tricky situations when parsing JSON with Swift's Codable.

This post shows two ways of achieving dependency injection in SwiftUI: using @EnvironmentObject or a View Model Factory.

A ViewModel full of promise

With the iOS 14 release Apple added a new way to experience your app's features called App Clips. Let's discuss how App Clips works and ways to integrate them into an existing app.

A beginner’s guide to @State in SwiftUI

There are a few variations when dealing with counting days. You need to ask yourself some questions beforehand.

Is there a way to present UIKit popovers from toolbar buttons managed by SwiftUI?

Learn how to consume C++ code in Swift

Part 4 in my series on charts

Remote configuration is a common practice in almost every app I have worked on. Sometimes these configurations can be large and the implications of a configuration change can be far-reaching while…

I wanted an option for user to toggle iCloud sync on / off for my own app AuthCat (2FA OTP app with iCloud sync).Some users may not feel comfortable sharing their data to cloud, or just prefer to not sync data between devices, so it is important to have an

Constraints in Core Data prevent duplicate entries without fetching for existing values. Configure entities by marking attributes as unique.

Formatting numbers into human-readable strings can often be tricker than expected. Let’s explore why that is, and what kind of tools and techniques that can be good to keep in mind when formatting different kinds of numbers.

A question that comes back often when using Coordinator pattern in iOS development is how to pass data between views. Today I’ll share different approaches for a same solution, regardless if you are using MVVM, MVC or other architectural design pattern.