Why animations polish user experience in iOS Swift

Introduction

Animations make apps feel smooth and alive. They help users understand what is happening on the screen.

When showing a new screen or page to make the change less sudden

When a button is tapped to give feedback that it was pressed

When loading content to show progress and keep users engaged

When moving or changing items to show how things relate or update

When drawing attention to important parts of the app

Syntax

iOS Swift

UIView.animate(withDuration: TimeInterval, animations: @escaping () -> Void)

This is the basic way to create animations in iOS using Swift.

You specify how long the animation lasts and what changes to animate inside the closure.

Examples

This fades out a view by changing its transparency over half a second.

iOS Swift

UIView.animate(withDuration: 0.5) {
  myView.alpha = 0
}

This moves a view 100 points to the right smoothly in one second.

iOS Swift

UIView.animate(withDuration: 1.0) {
  myView.frame.origin.x += 100
}

This makes a button grow slightly to show it was tapped.

iOS Swift

UIView.animate(withDuration: 0.3) {
  myButton.transform = CGAffineTransform(scaleX: 1.2, y: 1.2)
}

Sample App

This app shows a blue square. When you tap it, the square moves right and changes color to red smoothly over half a second.

iOS Swift

import UIKit

class ViewController: UIViewController {
  let squareView = UIView()

  override func viewDidLoad() {
    super.viewDidLoad()
    squareView.frame = CGRect(x: 100, y: 100, width: 100, height: 100)
    squareView.backgroundColor = .systemBlue
    view.addSubview(squareView)

    let tapGesture = UITapGestureRecognizer(target: self, action: #selector(animateSquare))
    squareView.addGestureRecognizer(tapGesture)
    squareView.isUserInteractionEnabled = true
  }

  @objc func animateSquare() {
    UIView.animate(withDuration: 0.5) {
      self.squareView.backgroundColor = .systemRed
      self.squareView.frame.origin.x += 150
    }
  }
}

Important Notes

Animations usually run on the main thread and should be short to keep the app responsive.

Use animations to guide the user's attention and make interactions clear.

Common mistake: animating too many things at once can slow down the app.

Summary

Animations make apps feel smooth and easy to use.

They help users understand changes on screen.

Use UIView.animate to create simple animations in Swift.