UniOne Email API vs. Courier

UniOne Email API is a software interface that allows developers and businesses to integrate email functionality into their applications, websites, or systems. It provides programming tools, protocols, and methods that enable seamless communication with email servers and services. With UniOne Email API, users can send transactional and bulk emails, manage subscriptions, track email interactions, and access other essential email features programmatically.

Courier is notification infrastructure for customer messaging, built for humans and AI agents. It sits between your app and every channel you send on: email, SMS, push, in-app inbox, chat, and webhooks. You send one request, and Courier works out where it goes, what it looks like, and whether the user wanted it at all. Teams use it for the messages a product has to send: onboarding, alerts, receipts, reminders, and account notices. You keep the providers you already pay for. Courier is the layer above them.