Drip Scripts - Create automated email sequences in 60 seconds
Mail Designer 365 - Discover Mail Designer 365, the easiest way to design mobile-optimized HTML emails, templates and newsletter designs. Your HTML email designer for Mac.
MailChimp - MailChimp is the best way to design, send, and share email newsletters.
Really Good Emails - A large collection of good product email design.
Campaign Genius - Send dynamic email content through any platform, instantly.
Polymail Sequences - Simple, powerful multi-stage email campaigns