In today's iOS ecosystem, users expect a seamless experience whether they're on a compact iPhone or a large iPad with multitasking. This module moves beyond single-device design and teaches you the professional approach to building universal apps that look and feel great everywhere. We will explore Apple's modern design framework, centered on the powerful concepts of Size Classes, Dynamic Type, and standard UIKit elements. <br> You will learn not just the theory behind adaptive design but also its practical application within Xcode. We'll start by understanding how Size Classes allow you to create flexible layouts that respond to different screen dimensions and orientations. You'll then get hands-on experience customizing your app's interface, creating unique layouts for iPad that take advantage of the extra screen real estate without breaking your iPhone design. By the end of this module, you will have the skills to create a single, elegant user interface that automatically adapts, ensuring your apps are polished, accessible, and professional on every device.

It's time to bring all your skills together and build your first fully functional iOS app from the ground up! In this project-based module, you will create "Window Shopper," a practical calculator that determines the work hours needed to afford a desired item. This project is designed to bridge the gap between learning individual concepts and understanding the complete app development lifecycle. <br> We will go far beyond basic drag-and-drop UI. You will learn how to create custom, reusable UI components, such as a currency-aware text field, and see your code render live in Interface Builder using @IBDesignable. More importantly, you will be introduced to a cornerstone of professional software development: unit testing. You will learn not only why testing is critical but also how to write your own tests to validate your app’s logic and prevent bugs. We'll connect the UI to the business logic, implement the calculations, and finalize the app with custom drawing and navigation. By the end, you won't just have a finished app; you'll have experienced the end-to-end workflow of a professional iOS developer.

Now that you've built the Window Shopper app, it's time to consolidate your learning and put your new iOS development skills to the test. This module is your opportunity to transition from following tutorials to building independently. There are no new video lectures here; instead, you will engage in two critical activities that mirror a real-world development environment: a practical coding challenge and a peer code review. <br> First, you will take on the challenge of building a brand-new "Unit Converter" app from scratch, applying everything you've learned about UI, logic, and user interaction. Then, you will participate in a discussion forum where you'll share your solution with your peers and provide constructive feedback—an essential skill for any collaborative developer. Finally, to help you benchmark your progress, you will be given the complete source code for the Window Shopper app, allowing you to compare your own work against a finished solution and identify areas for growth. This module is all about practical application and proving to yourself that you can build functional iOS apps.