What is the difference between a push notification and a text message?

A push notification comes from an installed app or a website the user subscribed to, and it is free to send. A text message (SMS or MMS) goes to a phone number through a carrier, reaches people who never installed your app, and costs money per message. Push needs notification permission; marketing texts need explicit SMS consent.

Do push notifications work when the app is closed?

Yes. The operating system receives and displays the notification, so the app does not need to be running. The user only needs to have allowed notifications for your app and to have the app still installed.

What is a good push notification opt-in rate?

Android apps usually see higher opt-in rates than iOS apps because many Android users granted permission by default before Android 13. On iOS, apps that ask with a clear primer at a relevant moment do much better than apps that ask on first launch. Track your own rate per platform and test the prompt timing. For tools that help with this, see our comparison of push notification services.

Back to Glossary

Mobile & Push

Push Notification

A short message an app or website sends to a user's device that appears outside the app, on the lock screen, in the notification center or as a banner, even when the app is closed.

Definition

A push notification is a message sent from a server to an app or browser on a user's device, delivered by the operating system's push service and shown outside the app itself. On iOS the message travels through Apple Push Notification service (APNs), on Android through Firebase Cloud Messaging (FCM), and in browsers through the Web Push protocol. A push usually has a title, a body, an optional image, and a tap action that opens a screen in the app or a web page. Users must allow notifications first: on iOS and on Android 13 and later the app has to ask for permission before it can show anything.

Why It Matters

Push is the one channel that reaches app users without them opening the app or their inbox. It works for time-bound moments that email is too slow for: a trial ending tonight, an order out for delivery, a streak about to break, a price drop on a saved item. Because a user can switch it off with one tap, push also punishes irrelevant messages fast. Teams that treat push like a bulk email channel lose their opt-ins, and with them the cheapest way back to a lapsed user.

How It Works

When the app starts, it asks the operating system for a device token and sends it to your backend or messaging platform. To send a push, your server calls the platform push service (APNs, FCM or a browser push endpoint) with that token, your credentials and a payload. The push service delivers the message to the device, and the operating system displays it according to the user's notification settings, Focus mode and the app's permission state. When the user taps it, the app opens to the screen named in the payload, often through a deep link. Tokens expire when users uninstall or reset their device, so senders remove tokens the push service reports as invalid.

Example

A language-learning app sends three kinds of push:

Transactional: "Your subscription renews tomorrow for $9.99."
Behavioral: "You are one lesson away from a 30-day streak." sent at the hour the user usually practices.
Lifecycle: "Your free trial ends in 24 hours. Keep your progress with Premium." triggered by a trial-started event from the billing system.

Each one opens a specific screen through a deep link instead of the app's home screen.

Best Practices

1Ask for permission after the user has seen value, ideally behind an in-app primer that explains what you will send
2Send push only for messages that are personal, timely or both, and route everything else to email or in-app
3Deep link every notification to the exact screen it talks about
4Respect the user's local time and keep marketing pushes out of the night hours
5Track opt-in rate, delivery, open rate and opt-outs per message type, not just total sends
6Remove invalid tokens promptly so delivery stats stay honest