MJML - The open source framework for responsive emails
Carrd - Simple, responsive one-page site creator.
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.
Landing Pages in MailChimp - Easy to build, custom landing pages for free
Templates by Email Monster - Hundreds of free, responsive email templates. Pick and edit.
Bumble - Bumble is a social network that allows you to feel empowered while you make those connections, whether you’re dating, looking for friends, or growing your professional network. One first move on Bumble could change your life.