iOS Safari supports Web Push Notifications for Progressive Web Applications (PWAs). To receive them, the PWA must be installed directly to the iOS Home Screen via Safari.
Standard Safari tabs or third-party browsers like Chrome (which use WebKit under the hood) cannot prompt or receive these push notifications.

Key Implementation Requirements

To successfully integrate push notifications on iOS, developers and users must meet specific technical and system requirements:

iOS Version: Requires iOS 16.4 or newer.
Web Standards: The web app must implement Service Workers, the Push API, and the Notifications API.
VAPID Keys: Your backend needs VAPID (Voluntary Application Server Identification) keys for secure push message authentication.
Standalone Mode: The permission prompt must be triggered by a direct user action (such as clicking a "Subscribe" button) while the PWA is running in standalone mode (installed on the Home Screen).

Step-by-Step User Workflow

For users to start receiving updates from your PWA:

Open in Safari: The user must open the target website using the standard iOS Safari browser.

Add to Home Screen: The user must tap the Safari Share button (the square with an upward arrow) and select "Add to Home Screen".

Launch the PWA: The user taps the newly created Home Screen icon to launch the app as a standalone web application.

Grant Permissions: Within the standalone app, the user interacts with the app's prompt (e.g., toggling notifications) and taps "Allow" when iOS requests notification permissions.

Developer Resources & Documentation

For comprehensive and step-by-step technical integration guides, rely on official resources and documentation:

Apple Developer Documentation: Review the cross-browser standards and backend requirements on the Sending Web Push Notifications guide.  https://developer.apple.com/documentation/usernotifications/sending-web-push-notifications-in-web-apps-and-browsers
