Courier is an all-in-one notification platform that offers easy access to messaging providers, flexible customization options, and advanced features such as retry mechanisms, comprehensive logging, and error handling. By integrating with various programming languages including Ruby, Go, Python, Javascript, Node.js, and React, Courier provides a unified interface for sending SMS messages, reducing the complexity of managing multiple APIs. The platform's focus on reliability, flexibility, and user preference management makes it an attractive option for businesses looking to centralize their messaging channels, with features such as customizable templates, batched daily notifications, and integration with customer data platforms.