Imagine you have a box that might have a toy inside, or it might be empty. An optional in Swift (the language used for SwiftUI) is like that box: it can either hold something (like a number, text, or data) or it can be empty (called nil in Swift). In SwiftUI, optionals help us deal…

When you’re first learning to code, you might have all of your code in one big, long file. And that’s perfect for being in the playground and learning how to code. Once you start building real apps, you’ll have so much code that it won’t be practical to use one big file. Functions let you…

SwiftUI is designed to simplify UI development by letting developers declare what the UI should look like, and SwiftUI handles the how of rendering and updating it. But while SwiftUI emphasizes declarative structures, functions still play a critical role. In fact, they’re one of the most powerful tools you have for writing cleaner, reusable, and…

Swift is Apple’s powerful and intuitive programming language. Like all programming languages, Swift handles different types of data by classifying the data into different types. One important characteristic of Swift is that Swift is a type-safe language. In simple terms, this means that once you declare a variable or constant with a specific data type,…

If you want to add in-app subscriptions to your SwiftUI app, RevenueCat is one of the easiest ways to do it. In this example, we’ll walk through setting up a freemium model where users can use our app’s core features for free and subscribe to unlock premium features at either $3.99 per month or $19.99…

Swift is a type-safe language, which means it helps you avoid mistakes by making sure the values you use in your code are always the right type. For example, if a function expects a number, Swift won’t let you accidentally pass in a string. This kind of safety makes your code more predictable and easier…