Courier provides a comprehensive solution for building a modern in-app notification center, catering to the demands of real-time updates, cross-platform synchronization, and multi-channel orchestration. By leveraging sophisticated infrastructure, including managed WebSocket for instant message delivery and cross-channel synchronization, Courier ensures a seamless notification experience across devices and platforms. It offers enterprise-grade audit logging, native SDKs for multiple platforms, and user preference management to comply with regulations like GDPR and HIPAA. Notably, companies like Twilio have chosen Courier over building their own systems, citing its robust infrastructure and ease of implementation. Courier also offers flexibility in integrating existing providers and supports incremental migration from current systems. This allows engineering teams to focus on core products by outsourcing notification infrastructure to a dedicated team of experts, thus simplifying the complexities of compliance, scaling, and provider redundancy.