Integrations

What is the Twilio Messaging API?

Twilio's Messaging API enables developers to send and receive SMS, MMS, WhatsApp, and RCS messages at scale across 180+ countries. While Twilio excels at reliable message delivery through carrier networks, modern applications need more than single-channel messaging. Courier acts as a provider-agnostic orchestration layer that activates messaging across Twilio and other channels from a single platform. You get intelligent routing, user preference management, and fallback logic without vendor lock-in.

Push notification fallbacks: email, Slack, and SMS

Route a message to email, Slack, or SMS when push can't deliver, add a backup provider per channel, and keep user preferences in charge, all from one send request.

Top 7 Push Notification Providers in 2025

Push notifications drive real-time engagement, but managing multiple providers creates integration complexity. Courier is provider-agnostic orchestration layer for Push, Email, SMS, In-App, and Chat. We evaluated 7 top push services—FCM for universal coverage, APNS for iOS reliability, MagicBell for in-app centers, plus Airship, Pusher Beams, Expo, and AWS SNS. Most apps need multiple providers like FCM + APNS + MagicBell. Instead of custom integrations, use notification orchestration for automatic failover and unified management across email, SMS, and chat channels.

Top 6 Email Service Providers for Transactional Notifications in 2025

Comprehensive guide to the 6 best email service providers for transactional notifications in 2025. Compare SendGrid for high-volume enterprise delivery, Mailgun for developer APIs and routing control, Resend for React-based templates, AWS SES at $0.10/1000 emails for cost efficiency, Postmark with <2 second delivery for critical notifications, and SMTP for universal compatibility. Learn why most teams need multiple ESPs, how to meet new SPF/DKIM/DMARC requirements for Gmail, Yahoo, and Outlook.

Courier + Segment: A Guide to Event-Driven Messaging

Courier's native, bidirectional Twilio Segment connection enables real-time event-driven messaging with engagement feedback loops. Trigger multi-channel notifications (email, SMS, push, in-app) from Segment track events like "Trial Started" or "Feature Used." Courier sends engagement data back to Segment for behavioral analytics. Build automated workflows with drag-and-drop editor, conditional logic, and channel fallbacks. Supports SendGrid, Twilio, and native Inbox components for comprehensive notification orchestration.

How to Send an SMS in Java

Send an SMS in Java using the Courier SDK with your existing Twilio account as the provider. Complete working code, step-by-step setup, and a direct Twilio comparison for when the orchestration layer is overkill.

New RudderStack integration: Create actionable data insights

Are you looking for a way to gain a clearer picture of your users and use that insight to improve your communication strategies? We've got some great news for you! Today, we're thrilled to announce an integration between Courier and RudderStack, a customer data platform (CDP) that allows businesses to collect, process, and route customer event data across product, marketing, and analytics tools for better decision-making. This integration builds on our recently improved integration with Segment and will further improve your ability to track your users' actions and take advantage of customer data stored in RudderStack to improve the notification experience for your users.

Smarter customer engagement flows with Courier’s new Segment integration

Courier can now be a source of events in Segment, allowing you to make the most of your multi-channel customer data. Which communications were successfully delivered? Which ones were opened and read? On what channels? These types of events generated in Courier can now be used to create custom user journeys. This step completes the integration of the two services: previously, [Segment was available as a data destination in Courier](https://www.courier.com/blog/courier-segment-integration-product-notifications). Now that the integration has come full circle, let’s have a look at how your organization can benefit from combining the two tools.

Building a Slack Integration for Your SaaS Notification System

Many organizations don’t quite know what to expect when building an integration for sending messages from their SaaS product to a Slack channel or a direct message.