What tools and technologies have you used for multithreading in your practice?

In iOS, for implementing multithreading, the following tools and technologies are most commonly used:

• Grand Central Dispatch (GCD) — a low-level API for managing task queues. It allows executing code asynchronously or synchronously on various threads, simplifying multithreading.

• Operation and OperationQueue — a higher-level abstraction over GCD, enabling creation of operations with dependencies, cancellation, and priorities.

• NSThread — an older way to create and manage threads, now rarely used but useful for understanding basics.

Example of using GCD to perform a task in the background and update UI on the main thread:

DispatchQueue.global(qos: .background).async {
    // Background task
    let result = heavyCalculation()
    DispatchQueue.main.async {
        // UI update
        self.label.text = "Result: \(result)"
    }
}

This approach helps avoid blocking the main thread and keeps the interface responsive.