In this project we’re going to build an app that lets the user import photos from their library, then modify them using various image effects. We’ll cover a number of new techniques, but at the center of it all are one useful app development skill – using Apple’s Core Image framework – and one important SwiftUI skill – integrating with UIKit. There are other things too, but those two are the big takeaways. Core Image is Apple’s high-performance framework for manipulating images, and it’s extraordinarily powerful. Apple have designed dozens of example image filters for us, providing things like blurs, color shifts, pixellation, and more, and all are optimized to take full advantage of the graphics processing unit (GPU) on iOS devices. Tip: Although you can run your Core Image app in the simulator, don’t be surprised if most things are really slow – you’ll only get great performance when you run on a physical device.