Notifications in iOS 12
iOS 12 makes it possible to send critical alerts. Critical alerts play a sound regardless of whether or not Do Not Disturb is enabled or the ringer switch is off.
With iOS 12, notifications can now modify their action buttons at runtime. Doing so makes it possible to display actions more relevant to the content of the notification and the user's interaction with it.
In order to help users to manage the many notifications they receive, iOS 12 can group notifications by app or by thread.
In iOS 12, a notification's custom user interface can include interactive controls.
iOS 12 can deep link to an app's notification management screen, making it easier for users to enable or disable specific types of notifications.
Provisional notifications allow apps to display quiet notifications without requiring the user to opt in. Quiet notifications do not play a sound and appear only in Notification Center. They provide a way for users to preview the notifications an app sends before deciding whether or not to allow or disallow them.