MailChimp - MailChimp is the best way to design, send, and share email newsletters.
ChatWhale - Gamify your customer communication and loyalty rewards
SendOut - Affordable email marketing for bloggers and influencers
LaunchKit - Open Source - A popular suite of developer tools, now 100% open source.
rasa.io - Get more from your email list.
Promoter - The Most Effective Way To Engage And Learn From Customers