IN-APP INBOX

Notifications that live inside your product.

A hosted notification inbox for your web app: stream new notifications over Server-Sent Events, track read and acknowledged state, and let users manage their own preferences.

Start with In-App Read the docs ↗

Transport: Server-Sent Events
Heartbeat: Every 15s
Severity levels: Info → Critical
Targeting: User · Role · Group · Tenant

What the In-App engine handles for you

Live stream over SSE

Clients subscribe to one Server-Sent Events stream with a heartbeat every 15 seconds. Reconnecting with Last-Event-ID replays recent notifications the client missed.

Read, unread, and acknowledge

Per-notification read, unread, and acknowledge actions, mark-all-read, and an unread-count endpoint for the badge on your bell icon.

Target users, roles, or groups

Address a single user, a list of users, a role, a group, or everyone in a tenant or application, from the same send call.

Severity, expiry, and preferences

Tag notifications from info to critical, let them expire when they stop being relevant, and let users set their own preferences.

TURNKEY IN-APP INBOX · ZERO WEBSOCKET BLOAT

The in-app notification center your users will actually love.

Stream notifications into your web app over Server-Sent Events. Every open tab gets the same live updates, clients that reconnect pick up what they missed, and there are no WebSocket servers to run.

Embed Style:

⚡ Dispatch Live Event:

VORTEX ANALYTICS PROv2.8-prod

2 Tabs Active · Synced

Alex Dev

Notifications3 unread

💳

Enterprise Renewal: $4,800.00

1m ago

Stripe subscription invoice INV-2026-09 paid successfully by Acme Corp.

🚀

Canary Rollout v2.14 Live

4m ago

100% traffic smoothly routed across 16 Kubernetes pods with 0 errors.

🛡️

Scoped API Key Rotated

18m ago

Key "gns_live_prod_992" promoted to primary. Old key expires in 48h.

⚡

High Ingestion Rate (12.5k/s)

1h ago

EU ingress gateway auto-scaled 4 additional delivery workers.

●Drop-in React Hook:const { notifications, unreadCount } = useInAppNotifications()

Zero WebSocket servers required

In-App · request

POST /api/v1/notifications
Authorization: Bearer <SENDRIN_API_KEY>
Content-Type: application/json
Idempotency-Key: invoice-2026-09-paid
{
  "event_key": "billing.invoice_paid",
  "channel": "in_app",
  "recipient": { "type": "user", "id": "usr_4821" },
  "data": { "invoice_id": "INV-2026-09" }
}

Supported providers

Built into Sendrin

No external provider is needed. Publish an in-app event template and integrate the authenticated inbox endpoints into your application. The inbox guide covers identity, streams, and read state.

Give your product an inbox without running WebSockets.

One API, every channel, full delivery visibility. Start free, no credit card required.

Start Sending — Free

Read the Docs ↗