Platforms State of the Union

Written by Stefan Herold

Description: WWDC 2019 Platforms State of the Union

  • App Store requirement to adapt to all screen sizes from Spring 2020
  • tvOS gets Multi-User support plus support for Xbox and Playstation game controllers


  • Less Code. Better Code. Everywhere. Declarative Syntax.
  • Round images by Image(name).clipShape(Circle()).shadow(radius: 3, y: 3)
  • CornerRadius by Image(name).cornerRadius(3)
  • Creating a label by Text("Done!").font(.headline).color(.gray)
  • Changing label to button by Button("Done!", action: done).font(.headline).color(.gray)
  • Automatic Spacing & Insets, Localizability, Right-To-Left, Dynamic Type, Dark Mode, ...
  • Animations are Repsonsive, Interruptable, Automatic with minimum amount of code
  • Build powerful layouts through composition leveraging VStack and HStack
  • Adopt ObservableObject for model objects that can change
  • Live Development Experience
  • Adopt PreviewProvider for views/view controllers (surrounded by #if DEBUG) to live-preview in canvas
  • Multiple previews with different configurations displayable on one canvas
  • Adopt SwiftUI gradually at your own pace


  • Introduction of Module Stability which ensures compatibility for binaries of current/future versions of Swift compiler
  • GitHub adds Swift Package support to the GitHub Package Registry
  • Swift Packages for apps on all platforms seamlessly supported by Xcode

Xcode 11

  • Add additional editors whenever and whereever you want
  • Use related content (Live View, Assistants, ...) in any editor of your workspace. They disappear automatically when there is no content.
  • Minimap enables straigt-forward code navigation. Highlights MARK declarations, Issues, Test Failures, ...
  • Add Documentation feature auto-adds missing function parameters
  • Refactoring also changes documentation parameters
  • Source-control history moves to the Inspector pane on the right side. Can now always be open.
  • Editor displays inline code-change comparison
  • TestPlans enable the developer to create many different test combinations (localizations, environment settings, sanitizers, devices). Works with Xcode Server!
  • Enable device conditions in Xcode: Network Link Conditioner, Thermal State
  • New app performance metrics for released apps: Battery Usage, Launch Time, Hang Rate, Memory Use, Disk Access
  • TestFlight user feedback lets users share screenshots and comments

macOS Catalina

  • Bring your apps to the Mac by just enable one checkbox in Xcode
  • Move kernel extensions out of the kernel into user space with DriverKit which improves macOS stability for all users
  • System volume will become read only. User data and apps are on a read/write volume.
  • New permissions for apps that want to do Keystroke Recording, Screen Capture, Screen Recording
  • New permissions for apps that want to access directories like Documents, Desktop, Downloads, iCloud Drive, Removable Media, Network Volumes


  • The watch becomes independent from the phone by running its own apps, by just checking a checkbox in Xcode
  • Independent apps are highlighted on the watchOS App Store
  • App Store has fully featured app descriptions. Apps are searchable by dictation and scribble. Direct download of the new, small bundles.
  • Notifications, CloudKit, Complication Pushes, Text Fields, Sign In With Apple
  • Streaming audio to the watch
  • SwiftUI support


  • New semantic colors that automatically update for the brand new Dark Mode
  • New set of adaptive materials and vibrant content filters with variable transparency which support ligh/dark content mode
  • Modal view controllers are now displayed as cards by default
  • Peek and pop redesigned to show previews with contextual actions
  • SFSymbols are 1500+ free, vector assets, variable scales and weights
  • Re-designed share sheet


  • Major enhancements to multi tasking by new UIWindowScene API
  • New SceneDelegate to manage multiple windows at the same time from one app
  • New state restauration system using NSUserActivity
  • PencilKit framework for customize drawing in your app
  • Major simplification in text selection. UITextInteraction API to fix conflicting-gesture issues
  • ScrollViewScrubbing: Grab and drag the any scrollview scroll indicator

Accessibility Features

  • Accessibility has been added to the iOS Quick Start guide
  • Accessibility has been moved one hierarchy level up into the Settings main menu
  • Accessibility sub-menus menu got icons for better discoverability
  • Voice Over can display a grid for better selectability. You can show accessibility labels and much much more. It's an incredible feature!
  • Showing accessibility labels via Voice Over completely changes how we can test them. They are now just displayed on screen!


  • Good Practice: Process user data on device whenever you can & Ask for permission when processing user data & Encrypt user data
  • Allow once is a new option when requesting location permission
  • Apps location usage shown on a map by apple from time to time
  • Sign in with Apple provides fast, easy sign in without tracking by tapping a Sign in with Apple Button and a quick FaceID
    • No more email address verification since apple already done this!
    • All AppleID-emails are protected by 2FA
    • Built in fraud detection
    • Apple provided email relays protect users real email address
    • Cross platform support: Works on Android and Windows devices (on the web)
    • No tracking by Apple

Machine Learning

  • Happens on-device
  • Engine is capable of 5 trillion operations per second
    • Image Saliency provides image heatmap
      • Highlights important objects and where users are likely to focus
      • Helps auto-cropping photos
    • Text Recognition
      • Search text from signs, posters and documents
      • Take advantage of the document camera capability from the Notes app
    • On-Device speech API with support for 10 languages
  • CoreML supports more than 100 layer-model types which brings e.g. breakthrough natural language processing to your apps
    • Core ML On-Device Personalization enables developers to update models from inside the app (in the background)
    • Create ML becomes a macOS app enabling users creating models without writing code
      • Choose from different model templates
      • Build multiple models with different data sets and define parameters of each
      • Real-time feedback on model training
      • Supports transfer learning (e.g. for image classification) which speeds up training
      • Experiment and preview models, e.g. use microphone to test sound classification models

Siri Shortcuts

  • Make them discoverable by adding the Add to Siri button to your apps
  • Apple made them conversational by adding Parameters
  • Shortcuts app is build into iOS and iPadOS
  • Added Automation which allows to set triggers for when to run specific shortcuts
  • Configurable 3rd-party actions enable combination of multiple actions (multi-step shortcuts)
    • Synced via iCloud to all of your devices


  • Integration of AR Quick Look with Apple Pay to try out clothes, glasses, and other products (and immediately by them)
  • Worlds largest AR platform
  • 3 technologies that make it easy to develop AR experiences: ARKit, RealityKit, Reality Composer
  • Reality Composer lets you layout AR experiences in 3D on macOS, iOS and iPadOs
  • RealityKit is a modern real-time 3D engine. Designed for AR. Easy integration with existing apps.
    • Uses physically based rendering, Data driven rendergraph, Multi-threaded
    • Access through native Swift API framework
  • ARKit 3
    • Simultaneous from and back camera
    • Motion capture by ML algorithm
    • People occlusion detection by ML algorithm


  • Modern high performance (100x OpenGL) GPU programming. Low overhead. Easy to use.
  • Core layer under all of Apples frameworks: UIKit, AppKit, Core Animation, SpriteKit, RealityKit, ARKit, MapKit, WebKit, Core ML, Create ML, VisionKit, Core Image, Camera Processing
  • Full support in iOS Simulator brings major performance improvements
    • Metal Compute provides building blocks for general purpose computation: Shading Language, Compiler, Compute Encoding, Metal Performance Shaders,
    • Metal Tile Shading combines compute shaders and fragment part into one highly-efficient render pass
    • Metal Indirect Compute Command Encoding lets you build GPU compute commands right on the GPU
  • Amazing Metal-based, animated Raytracing demo with computationally expensive multi-reflections and more
  • "Built for Pros" 😅

This note was originally published at

Missing anything? Corrections? Contributions are welcome 😃


Written by

Stefan Herold

Stefan Herold

iOS Developer a.d. 2009 • iOS / OSX Enthusiast • WWDC19 • Past: flinc, Deutsche Telekom, NOLTE&LAUTH • Passionate Mountainbiker