Ultimate Catalyst Guide

How does the iOS app lifecycle work on macOS?

released Fri, 05 Jul 2019
Swift Version 5.1

The "Taking iPad apps for Mac to the Next Level" talk at WWDC 2019 has a fantastic overview of all the changes. Here is a brief overview:

  • The UIApplication lifecycle is fully supported on macOS
  • The sequence is the same as on macOS
  • State changes, however, do affect the Mac less, as are almost always Foreground + Active on macOS.
  • Apps only enter background during termination and inactive when launching in the background.
  • Your app should still take App Napp into account
  • Background modes are allowed to finish when an app closes. The background tasks continue even though the app is already not visible anymore to the user
  • Apps are not killed when they consume too much memory
  • Background audio is not supported because users expect audio to stop when they quit an app

So, in short, your app is always in Foreground + Active except when it is (mostly) launching or terminating.