testmail.app VS Smtp4dev

Testmail.app - Automate end-to-end email tests with unlimited mailboxes and a GraphQL API. 100 emails/month free forever, unlimited free for open source. - Source: dev.to / almost 3 years ago

I initially checked if it's a phishing link. But it wasn't. Found this funny. If you ever find yourself in a position to test your newly written email module, try out testmail.app (not a sponsored link). Source: almost 3 years ago

Depends on the infrastructre setup, but if you're able to specify smtp server the backend will use you can you something like https://github.com/mailhog/MailHog or https://github.com/rnwood/smtp4dev to catch any sent email, regardless of email address and read it via the respective api. Both mailhog and smtp4dev have decent api documentation. Source: about 1 year ago

If so you could check out smtp4dev, it gives you a locally hosted client that you can use to intercept any mail send out by your app and displays them in a nice web based gui interface so can see what they look like. Source: almost 2 years ago