What Are Push Notifications?
Push notifications are short messages an app or a website sends straight to a user's lock screen, notification tray, or browser, without the user having to open the app at that moment. Unlike an email or a text message, a push notification travels through a direct channel between the company's server and the device, as long as the user granted permission first.
Almost every app you use daily — banking, delivery, social media, ecommerce — relies on push notifications to tell you your order shipped, someone messaged you, or there's an active promotion. Used well, push is one of the highest-reach channels available, because it doesn't depend on someone checking their inbox or answering their phone.
How Push Notifications Work
The flow behind how push notifications work is the same whether it's a mobile app or a website, though the technical players change:
- The user grants permission to receive notifications (an explicit prompt from the browser or the operating system).
- The device generates a unique identifier (a token) and registers it with a push messaging service: Firebase Cloud Messaging (FCM) for Android, Apple Push Notification service (APNs) for iOS, or the browser's own push service for the web.
- The business stores that token, linked to the user, in its own database.
- When it wants to send a message, the business sends it to that messaging service, not directly to the phone.
- The messaging service delivers the message to the device, even if the app is closed, and the operating system displays it.
That's why a notification can arrive seconds after an event fires — an approved payment, a driver on the way — without the user having the app open at that moment.
Mobile Push vs. Web Push Notifications
They share a name, but they're not the same thing:
- Mobile push: requires the user to have the native app installed (iOS or Android). It routes through APNs or FCM and can include images, action buttons, and custom sounds within the same message.
- Web push notifications: sent from a website with nothing to install, using the browser's Web Push standard (Chrome, Firefox, Edge, and Safari all support it). The user grants permission once, directly in the browser, and keeps receiving messages even with the tab closed, as long as the browser is still running in the background.
The advantage of web push notifications is that they don't depend on the user downloading an app: any visitor to an online store or a blog can subscribe in seconds. The trade-off is that, on mobile, they depend on the browser and on the operating system allowing background processes, which varies across Android manufacturers and iOS versions.
Push Notification Examples by Industry
A few push notification examples already in use across industries:
- Ecommerce: an alert that a wishlist item dropped in price, or a reminder about an abandoned cart.
- Delivery and logistics: real-time order status, from "confirmed" all the way to "your driver has arrived."
- Banking and fintech: an alert for a charge or deposit, or a warning about a login attempt from a new device.
- Salons, clinics, and gyms: an appointment reminder or a membership renewal notice a day ahead.
- Media and content: an alert about a story relevant to that user's interests, not every new publication.
The pattern behind the examples that actually work is the same: the message answers something the user already wanted to know, not something the business wanted to announce.
User Permission: The Foundation of Everything
No push notification reaches anyone without the user authorizing it first, on mobile or on the web. The browser or the operating system shows a permission prompt, and if the user clicks "block" or "don't allow," that channel stays closed for that business until the user manually reopens it in their settings.
That's why the moment you ask for permission matters as much as the content of the message itself. Asking the instant someone lands on your site, before they understand what they'd be signing up for, usually ends in a rejection that's hard to reverse. Explaining first what kind of alerts they'll get — and only then triggering the browser's or the OS's native permission prompt — raises the odds they'll accept.
Segmentation: The Right Message for the Right Person
Sending the same notification to your entire user base is the fastest way to get people to tune it out or, worse, revoke permission altogether. Segmentation fixes this by grouping users by actual behavior:
- By activity: users active in the last 7 days get different messages than someone who hasn't opened the app in a month.
- By funnel stage: someone who abandoned a cart gets a reminder; someone who already bought gets shipping updates, not another promotion.
- By stated preference: if a user picked interest categories at signup, their notifications should respect that choice.
- By location or time zone: sending a promotion for a physical store only to users nearby, and at a reasonable time in their own time zone.
This segmentation usually draws on the same data already living in the company's CRM, cross-referencing purchase or interaction history with the rules that decide which message each group receives.
Best Practices for Push Notifications People Don't Mute
Businesses that keep permission rates high tend to follow similar rules:
- Controlled frequency: set a cap on notifications per day or per week, instead of sending one every time there's "something to announce."
- Actionable content: every message should give the user something to do or something they needed to know, not generic filler.
- Respected timing: no notifications at midnight unless it's genuinely urgent, like an unrecognized charge.
- Real personalization: use the user's name, city, or history when it adds something, without forcing it when it doesn't fit.
- An easy way to fine-tune: a user who can adjust which types of notifications they get — instead of only "all or nothing" — takes longer to turn them off completely.
These rules are easier to enforce when sending is tied to defined workflows instead of someone triggering each campaign by hand; the same automation principles already used elsewhere in the business apply directly to push messaging.
Frequently Asked Questions
What are push notifications, exactly?
They're messages a server sends directly to a user's device or browser through a push messaging service (APNs, FCM, or the browser's Web Push), without the user having the app or the site open at that moment, and only if they granted permission beforehand.
What's the difference between mobile push and web push?
Mobile push requires a native app installed and routes through APNs or FCM; web push is sent from a browser with nothing to install, using the Web Push standard, and the user subscribes with a single click on the site.
Why do users stop receiving my push notifications?
Almost always because they revoked permission in their browser or phone settings, or uninstalled the app. The most common reason behind that decision is being overloaded with messages that weren't relevant.
Do web push notifications work in every browser?
The major browsers — Chrome, Firefox, Edge, and Safari — all support the Web Push standard, though the exact experience can vary slightly by browser and operating system, especially on mobile devices.
Do I need an app to send push notifications to my customers?
No. You can start with web push notifications straight from your own site, without asking anyone to install anything; a native app expands what's possible (deeper personalization, working even with the browser closed), but it isn't a requirement to get started.
If your business needs to reach customers at the right moment — an order that's ready, an appointment to confirm, an abandoned cart — without building the messaging infrastructure from scratch, at AISDC we build push notification systems for apps and websites, with segmentation and automation connected to your existing business processes.