
Emailens
7.7#3 in email testing softwareFrom $9 a monthFree planWebAPIExtensionSelf-hosted
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Emailens may suit hobbyists, individual developers, freelance developers, indie hackers, and creators working with HTML email. It offers both a web interface and developer integration options.
Mailgun suits teams that need API- or SMTP-based email sending, tracking, webhooks, and inbound routing. It can fit users seeking a free starting plan or larger listed sending allowances.