MailClark - The Slack bot for external communications

Yesware - Sell smarter with email tracking and more

iDoneThis - iDoneThis The fun, easy way to get stuff done. Every day we’ll email your team to ask, “What’d you get done today?” Just reply to our email. The next day, everyone gets an email with the team's accomplishments

Mixmax - At Mixmax, our mission is to change how the world communicates. We’re an email productivity platform that helps sales, customer success, and recruiting teams do their jobs better.

PigeonBot - Send emails via Slack with the /email command

SalesLoft - The simpliest way to build the most accurate and targeted lists of leads on the internet