MJML - The open source framework for responsive emails
OptinMonster - OptinMonster helps to convert abandoning website visitors into subscribers and customers.
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.
OptiMonk - OptiMonk is the most powerful Onsite Retargeting platform, that helps you increase the conversion rate of your site, and get more leads by recovering lost visitors.
Templates by Email Monster - Hundreds of free, responsive email templates. Pick and edit.
Growthmysales - Increase e-commerce sales, grow email lists, and engage visitors effortlessly with our 5-minute simple popup builder.