A push notification is a short message sent from an app's server to a user's device, displayed even when the app is not open.
What is a Push Notification?
Push notifications typically cover a handful of trigger types, including transactional updates, social or activity alerts, behavioral win-back messages, promotional offers, and live-event alerts, and most apps run several of these categories side by side. They rely on the platform's own notification service, such as Apple's or Google's push services, which means delivery and formatting are bounded by what that platform allows rather than by the app itself. Users must explicitly opt in before an app can send push notifications, and they can revoke that permission at any time from their device settings, which makes relevance the deciding factor in whether the channel keeps working. A common variant is the rich or interactive push, which lets a user reply or take an action directly from the notification without opening the app.
Why Push Notifications Matter
Push is the only channel that reaches a user who is not currently in the app and did not open an email. For a user retention team, that makes it the primary tool for bringing lapsed users back and for turning a one-time visit into a habit. For a product team, it is the delivery layer for time-sensitive events: a reply to a comment, a new message, a live stream starting, an order update. The same reach is also the risk. Irrelevant or excessive notifications lead users to disable push or uninstall the app, so the practical work is deciding which events are worth interrupting someone for, and letting users control the rest.
Types of Push Notifications
Push notifications differ mainly by what triggers them and who they are for. Most apps use a mix, and the highest-performing category is almost always the one triggered by other users.
| Type | Trigger | Example | Typical purpose |
|---|---|---|---|
| Transactional | A system event tied to the user | Order shipped, payment received | Inform |
| Social or activity | Another user's action | Someone replied to your post, a new message in your group | Re-engage |
| Behavioral | The user's own inactivity or milestone | You have not checked in for 7 days | Win back |
| Promotional | A marketing campaign | 20% off this weekend | Convert |
| Live event | A scheduled or real-time moment | Stream starting now | Drive attendance |
Performance is measured with a small set of metrics: opt-in rate (share of users who allow notifications), open rate (share of delivered notifications that are tapped), and the downstream metric the notification was meant to move, such as session starts or Daily Active User (DAU). Worked example: an app sends a "new reply to your comment" notification to 40,000 users with push enabled. 6,000 tap it, an open rate of 15%. Of those, 4,800 perform another action in the session. If the app's baseline conversion from open to action is 60%, this notification is performing above baseline at 80%, which tells the team that social triggers are worth prioritizing over promotional sends.
Push Notifications and social.plus
Social activity generates the most relevant notification triggers an app can have, because the content comes from people the user already interacts with. social.plus provides engagement infrastructure, including feeds, in-app chat, groups, live streaming, and stories, through SDKs, APIs, and UIKit, and the events those features produce, such as replies, mentions, new messages, and streams going live, are the events apps most often surface through push. Brands using social.plus features report engagement rates of 20-50% and retention lifts of 10-35%, and notifications driven by real user activity are one of the mechanisms behind those numbers.
Key Takeaways
- A push notification is a server-sent message displayed on a user's device even when the app is closed, and it requires user opt-in.
- Notifications triggered by other users' actions generally outperform promotional sends because they are relevant by definition.
- Measure opt-in rate, open rate, and the downstream action each notification is meant to drive, not send volume.
- Give users granular control over notification types to protect the opt-in rate over time.