Really Good Emails - A large collection of good product email design.
MailChimp - MailChimp is the best way to design, send, and share email newsletters.
Email Kick - Email designer and analytics for your transactional emails.
Brevo - Innovative online Email Marketing solution to manage your contacts, create & send your newsletters and track your results. More than 80 000 clients. Best prices and attractive features.
Stripo - Stripo is an all-in-one email design platform. We enable our clients to build emails of any complexity, including interactive AMP emails, really fast and easy.
Campaign Monitor - Email marketing software built for designers and their clients to run successful email campaigns.