What Are Push Notifications?

This post will break down what Push Notifications really are, how they work, why they are used, and how they communicate with push notification services.

Randy Steele • Apr 8, 2021

What Are Push Notifications?

What Are Push Notifications?

Push Notifications in Mobile Apps

Push notifications are automated clickable messages that are sent by an application on your mobile device. Application developers can send push notifications at any time. It is important to note that you do not have to be using the app to have a notification delivered to you.

Push notifications can look a lot like text messages, however, they only reach users who have installed the particular application. Each mobile platform has support for push notifications and has its own services that handle them.

It’s also important for app developers to be cautious when deciding which users should receive which push notification. If a user gets too overwhelmed or annoyed, it may lead them to delete your app or mute notifications, which in turn, could result in them using the app less often, or worse, abandoning it altogether.

What is Takes to Deliver A Push Notification?

There are three major contributors when it comes to delivering a push notifications:

  1. Operating System Push Notification Service or OSPNS - Each operating system has its own push notification service.

  2. Application publisher - The app publisher, such as Google Play Store or Apple App Store, must enable push notifications on their app with the appropriate OSPNS.

  3. Client App - The operating system-specific app gets installed on a user’s device and it receives incoming notifications.

How do Apps Communicate With the OS Push Notification Service?

Push Notification

Once an app is registered with the operating system push notification service, the service then provides the app publisher with an application programming interface (API). This is how the app communicates with the OSPNS.

Next, the publisher will add an SDK to the app, this is code that is specific to the push notification service. Once these steps are complete the app is ready to be uploaded to the app store.


  • June 2009 - Apple launched Apple Push Notification Service. This was the first push notification service ever!

  • May 2013 - Google introduces “rich notifications” these types of notifications can contain images as well as action buttons. We’ll get more into actionable push notifications later but just know that they allow the user to take immediate action from the notification such as, replying to a message, open an app, play a video or song or even mark a message as read, which is a pretty common feature for chat apps nowadays.

  • September 2014 - Apple added interactive buttons, these buttons allow users to send a response immediately, soon after this Apple launched push notifications for the Apple Watch.

The Path of Push Notifications

iOS Push Notification Path

iOS Push Notification Path

Let’s start at the beginning. In order to receive a push notification, you must have that particular app installed on your device. Once the app is installed, you may be prompted to “allow” notifications (this depends on the operating system platform).

You will then start to receive push notifications on your device when certain actions happen, such as when you receive a new message or friend request, or when there is a new post.

Each mobile operating system (iOS, Android, Fire OS, Windows) has its own operating system push notification service or OSPNS. The application publisher enables OSPNS and uploads the application to the specified app store.

The application publisher can then compose a manual message through a message composer or the app publisher can set automated messages via the API. Then the publisher can define the audience and event that the push notification will be sent on.


There are some strategies that most app publishers will use when they are designing their push notification settings.

  • Match user data across all channels - This means web & mobile combined.

  • App publishers want to make it easy for users to share content across several social media sites like Facebook, Twitter, Instagram, tiktok, and others.

  • App publishers want to encourage users to opt-in by providing value with push notifications. This could be a variety of items such as a discount or free trial for “pro” or paid services or extra credits to use (if that applies to the particular app)

  • Keep customers engaged by creating an optimized app experience.

Why Do Push Notifications Exist?

Push Notificantion in Android OS

I like to think of push notifications as updates. They should provide value and convenience to the users of your app. If I have an app on my phone to manage my emails, I might want to receive a push notification anytime I receive a new email. It’s an easy way to get an update on my interests without having to proactively search for it.

Push notifications are a way for application developers/publishers to communicate directly with their users. Push notifications can be used for countless reasons such as:

  • Promotions

  • Notify current users of a new service or feature

  • Notify users of a recent update to the app

  • Improving customer/user experience

  • Send receipts

  • Send links to current users linking them to other channels (social networks, websites)

Actionable Push Notifications

Actionable Push Notifications

Actionable Push Notifications

A somewhat newer feature of push notifications are actionable push notifications these type of push notifications allow you to - you guessed it - perform certain actions. Some examples of these are marking a new chat message as read, or reply to the chat message directly from the actionable push notification.

Peer to Peer communication

Push notifications have many applications but one of the major conveniences of push notifications is in real-time communication apps like CometChat and WhatsApp.

We live in a largely digital world so real-time communication is important. In a chat application push notifications could be extremely useful. I could envision a push notification for a message that couldn't be delivered, a message that has been read, a reply to a conversation, when a user leaves a conversation, and a notification for when you have been disconnected from the chat service or app.


In this tutorial, we covered in detail what push notifications are. We also discussed that each operating system (Apple(iOS), Android, Amazon Fire OS) have their own push notification services. When apps are connected to these services that is what gives them the capabilities to send and manage push notifications.

Checkout more of our content on push notification -

  1. How to Add Push Notifications to Your Android Chat App Using Kotlin

  2. How to Add Push Notifications to an Angular Chat App

  3. How to Add Push Notifications to Vue Chat App

  4. How to Add Push Notifications to a React-based Chat App

**About Author
**Randy is a Full Stack Software Engineer that studied at Flatiron School. My strongest technical skills are Ruby, Ruby on Rails, JavaScript, React/Redux and PostgreSQL. He enjoys learning new technologies and expanding his development skills whenever he gets a chance. When his face isn’t buried in the terminal he loves exploring new places, traveling, live music, and camping.

Randy Steele


Randy is a Full Stack Software Engineer that studied at Flatiron School.

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