MailReach.co - The #1 email warming service to improve your deliverability by generating realistic and meaningful engagement to your emails. Easy-to-use solution to help you land in the main inbox instead of the spam folder.
PopcornNotify - Send simple emails and text messages from one API
Mailwarm - The email warm-up tool.
MailerSend - Better transactional emails for teams.
Warmup Inbox - Warmup Inbox is a tool that automates the process of warming up your email inboxes, raising your sender reputation and inbox health automatically.
PigeonBot - Send emails via Slack with the /email command