Push Notifications: When and How to Use Them in an App

What push notifications are and how they reach a phone

Push notifications are short messages an app can send to a phone even when the app is closed. Sent for a good reason they bring people back to something useful. Sent carelessly they get switched off.

Push notifications are short messages an app sends to a user's phone, even when the app is closed. Send them only for things the user asked for or needs to know soon, such as order updates, bookings or replies. Ask permission after the user has seen what the app does, say what they will receive, and let them choose which types to get.

Push notifications are short messages that an app's server sends to a user's phone. They appear on the lock screen or as a banner, even when the app is closed. They are different from messages shown inside the app while it is open. On iPhone, and on Android 13 and later, the person has to allow them first.

The route has four steps. The app asks the phone's operating system to register it and receives a token that identifies that app on that phone. The app passes the token to your server. When something happens, your server sends the message and the token to the platform's push service, which Apple runs for iPhone and Google runs for Android. That service passes the message to the phone.

Delivery is never certain. Apple's documentation says the system makes every attempt to deliver notifications promptly but does not promise to. A push notification should therefore never be the only way a user learns something that matters, such as a failed payment. Show the same information inside the app as well.

Three other things are often confused with push notifications.

• Local notifications are scheduled by the app on the phone itself, with no server involved. A reminder the user sets for an appointment is one example. They need the same permission.
• In-app messages appear only while the app is open. They need no permission, which makes them a good place to explain a feature before you ask for permission.
• SMS and email reach people who have not installed the app. They follow separate consent rules, and those rules differ by country.

When push notifications are worth sending

Send a push notification when the message is useful to that person, relates to something they did or asked for, and is worth reading before they next open the app. If one of those is missing, use another channel or send nothing.

Apple's UX writers suggest asking three things before you write any notification.

• Does it need to be sent right now?
• Does it save the person from opening the app?
• Does it say something you have not already told them?

The table sorts common message types by what to check before you build each one.

The platforms set limits. Apple's App Review Guidelines say push notifications must not be required for the app to function and should not carry sensitive personal or confidential information. They also say push should not be used for promotions or direct marketing unless the customer has explicitly opted in through consent language in the app, with a way to opt out. Android's design guidance lists things to avoid, including advertising another product, sending to people who have never opened the app, and nudges with no direct value, such as telling someone you have not seen them for a while.

Consent rules for marketing messages differ between the USA, UK, UAE, Australia, Singapore and Japan, and they change. Ask a lawyer before you send promotional messages to customers in any country. Check the current store documentation too, because both stores update their rules.

How to ask for push notification permission properly

Ask when the person can see why notifications would help, not on first launch. Apple's guidance is to avoid presenting permission requests the first time people open an app. Android's documentation says to let users get familiar with the app first, and suggests starting the request from a user action, such as tapping an alert bell or following an account.

1. Let the person reach a point of value in the app, such as placing an order or booking a slot.
2. Choose a moment when a notification would obviously help, for example just after the order is placed.
3. Say in one plain sentence what they will receive. "Updates about this order" is clearer than "stay in the loop".
4. Show the system prompt only after the person agrees to the idea. On iPhone the system prompt appears once, and if the person declines, the way back is the Settings app. Many teams show a short screen of their own first, with a "Not now" choice, so that the one system prompt is used at the best moment. Do not style that screen to look like the system prompt.
5. If permission is declined, carry on without it. Apple's guidelines do not allow an app to require people to switch on notifications in order to use it.
6. Keep a settings screen in the app that shows the current state and explains how to change it.

Apple also offers a quieter route called provisional authorisation. The app can begin delivering notifications without showing the prompt first. They arrive quietly, and each one carries a choice to keep or turn them off. This suits apps whose value is hard to explain before the person has seen a few messages. It also means your first messages need to be good.

On Android 13 and later, notifications are controlled by a runtime permission, and an app that targets that version decides when to show the prompt. Before Android 13, apps could send notifications without a prompt. Check the current documentation for how the Android versions your customers use affect your app.

How often an app should send push notifications

There is no standard number, and anyone who quotes one for every app is guessing. Frequency depends on the kind of message. A message caused by something the user did, such as an order update, goes out when the event happens and needs no limit. A message you choose to send, such as an offer or news, needs a cap that you set, write down and enforce on your server.

• Separate the types. Give order updates, messages from people, reminders and promotions their own settings, so someone can turn off offers and keep delivery alerts.
• Set a weekly limit per person for messages you start, and count every type of promotional message against it.
• Send in the person's local time, and avoid the middle of the night unless the message is urgent.
• Replace or group notifications about the same thing. Android's guidance suggests updating an existing notification instead of posting a new one, and grouping when you must send several.
• Do not send to people who have never opened the app. For people who have gone quiet, use another channel or send nothing.

Both platforms give users control over how disruptive a notification is. On iPhone, an app can mark a notification as passive, active, time sensitive or critical. Apple describes time sensitive as for cases that need immediate attention, such as account security and package delivery, and warns against overusing it. Critical alerts need a special entitlement from Apple. On Android, every notification belongs to a channel, which the settings screen calls a category. Once a channel is created, only the user can change how it behaves, so choose channel names and importance levels with care the first time.

Signs of too many notifications are people switching them off in the phone's settings, uninstalling the app, and store reviews that mention the noise. Apple's developer material warns that a stream of uninformative notifications can lead people to turn them off or delete the app.

Writing a push notification people act on

Lead with the fact, name the thing and point to one action. Tapping the notification should open the screen it talks about. Android's design guidance says so directly, and Apple advises that a notification should carry enough information to be useful by itself, not just serve as a hook into the app.

Keep the lock screen in mind. Anyone who can see the phone can read the notification, so leave out balances, health details and anything private. Apple's guidelines say not to send sensitive personal or confidential information in push notifications.

If your users are in several countries, write each language properly rather than translating word for word. Text length changes between languages, and Arabic reads right to left, so test the real notifications on real phones set to each language. Send in the user's local time zone.

What to decide with your developer before notifications are built

Decide what notifications the app will send at the start, in the app brief, not after the build. For a first version, one or two message types tied to the main task are enough. Our guide to what to build in the first version of your app explains how to cut a feature list down, and a full campaign tool rarely belongs in it.

These questions are worth putting to the developer.

• Which events on the server trigger a notification, and what happens if the same event fires twice?
• Which message types will there be, and how does a user switch each one off?
• Where does the permission request sit in the first-run flow?
• What does the app do when permission is declined, or switched off later in the phone's settings?
• Which push service carries the messages, who runs it and where is the data stored? Apple and Google run the platform services. Many teams add a third-party service on top, and its privacy terms and pricing model become part of your running costs.
• How will you measure results, for example how many people allow notifications, tap them and switch them off?

If the app is built with Flutter or React Native, notifications still go through Apple's and Google's services. The framework adds a library between your code and them, so ask which library is used and who maintains it. The guide to native, Flutter and React Native covers that choice.

The permission flow is a design decision, so raise it at the design stage of the mobile app development process, not during the build. Notifications also touch your store listing. Reviews are public, and an app that feels noisy tends to collect complaints there. The app store optimisation basics guide covers the listing and how reviews fit in. If you want a developer to plan this with you, the mobile app development service page describes what Liftup builds.

Common push notification mistakes

• Asking for permission on first launch, before the person has seen what the app does.
• Sending one message to everyone when only some of them care.
• Making promotion the default reason to send.
• Treating a push notification as the only record of something important.
• Putting private details on the lock screen.
• Inventing urgency, such as a deadline that does not exist.
• Ignoring time zones, languages and quiet hours.
• Never testing what happens when permission is declined.

Questions and answers

What are push notifications?

Push notifications are short messages an app sends to a person's phone. They appear on the lock screen or as a banner even when the app is closed. They travel through Apple's service for iPhone and Google's for Android. The person gives permission on iPhone and on current versions of Android, and can switch them off later in the phone's settings.

How often should an app send push notifications?

No number suits every app. Messages caused by something the user did, such as an order update, go out when the event happens. Messages you choose to send, such as offers, need a weekly cap per person that you set and enforce. If people start switching notifications off, the cap is too high.

How do I ask for push notification permission properly?

Wait until the person has seen what the app does, then ask at a moment when a notification would obviously help, such as just after an order. Say in one plain sentence what they will receive before the system prompt appears. Do not make the app depend on a yes.

What happens if someone says no to notifications?

The app keeps working but cannot send notifications. On iPhone the person has to change the choice in Settings, so do not keep asking. Show the information inside the app instead, and explain on the app's settings screen how to switch notifications on.

Can I send marketing messages by push notification?

Apple's App Review Guidelines allow promotions by push only after the customer has explicitly opted in through consent language in the app, with a way to opt out. Android's design guidance advises against advertising another product this way. Consent rules for marketing also differ by country, so ask a lawyer before you launch.

Are push notifications the same as SMS or email?

No. Push needs the app installed and permission given. SMS and email reach people without the app, but they have their own consent rules and their own limits. Many businesses use more than one channel, with push for time-sensitive items and email for longer messages.

Will every push notification be delivered?

No. Apple's documentation says delivery is not promised, and a phone that is off, offline or restricting background activity may receive a message late. Show important information inside the app as well, so nobody depends on a notification alone.