Implement pre-fetching in your table views and collection views.
Update to Swift 4.2 — should be able to be handled 100% by the converter tool.
Notifications for your app are grouped by default — if you need to customize the behavior of grouping, add a thread identifier to your push payload.
To support the new automatic passwords, tag your password fields as either an existing/login password field, or a new/sign-up password field.
Make sure you are using safe area insets.
Add support for Siri Shortcuts [overview given here — covered in-depth in other sessions].
Scroll performance is improved by default due to CPU improvements and changes to the pre-fetching implementation.
Reducing the amount of memory your app uses, especially avoiding requesting large chunks at once, can improve speed. If your app requests more memory than is currently designated as “free”, then the system needs to go free up some more memory from other apps in the background, which takes some time.
Auto-layout performance has been greatly improved — in several cases going from an exponential growth down to linear as more views are added.
Swift 4.2 has moved types, constants, and functions inside of the relevant classes.
Introduces a new API that allows you to deep link directly to your existing granular notification settings in the app from a notification.
Siri Shortcuts make it easy to get common actions out of your app and make them accessible via Siri [more coverage in other videos].