mobile/how-does-a-push-notification-find-your-phone-when-the-app-is-closed.md

How does a push notification find your phone when the app is closed?

Mobile · 5 min read ·

A push notification does not come from your app. Your phone keeps one connection to a service run by Apple or Google, and your app's server hands that service a message addressed to a device token.

This article follows the message hop by hop, explains what happens when the phone is offline (storing, expiry, merging), and lets you try the rules in a small simulator.

A server, the Apple or Google push service and a phone joined by dashed lines, showing a message travelling to the phone

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