HTMLEmail.io - Responsive HTML email templates for startups & developers
MJML - The open source framework for responsive emails
Templates by Email Monster - Hundreds of free, responsive email templates. Pick and edit.
Email Design System for Sketch - Sketch file with 10 email templates for designers
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.
Getform - Smart form endpoints. The modern way to build the form backend.