Two-Factor Authentication
2FA (or two-factor authentication) is a security feature that requires a user to provide two forms of identification before they can access a system or application. This is typically achieved by requiring a password and a time-based one-time password (TOTP) generated by an app on a mobile device. This prevents unauthorized access to accounts even if an attacker has obtained the user’s password.
SMTP transaction logs
Every incoming message stored by Mailinator includes the SMTP transaction log produced during delivery. The SMTP log captures the SMTP conversation between the sending server and Mailinator, including protocol-level commands, response codes, and per-step timing information in milliseconds. This data is useful for debugging delivery failures, diagnosing slow relays, and comparing behavior across sending providers.
Streaming inbox feed
If you want to see incoming messages in near real-time you can use Mailinator's Streaming feed functionality. The feed uses a websocket-backed stream to show newly received messages without polling or refreshing the page.
Single Sign On
Mailinator Enterprise subscriptions support Single Sign-On (SSO) using SAML. 
Mailinator Universal IDP
Mailinator Universal IDP is a standards-compliant OpenID Connect (OIDC) Identity Provider built for testing SSO integrations. Use it in development, staging, QA, and automated test environments when you need to verify an application's OIDC login flow without configuring a production identity provider or creating real user accounts.
Webhooks
Mailinator allows you to HTTP Post or Webhook messages into your Private Domain. This is extremely convenient for testing as now all your test emails, SMS messages, and Webhooks will reside in the same place and are accessible via the same Web Interface, API, and Rule System.
Webhooks with Twilio
Mailinator applies specific mappings for services that commonly publish webhooks.