MailChimp Snap - Send simple, photo-based email campaigns from your phone.
GMass - GMass allows you to easily schedule emails, send out mass emails and mail merge campaigns and more with Gmail! Click here to learn about more features!
Pico - A stupidly simple and blazing fast, flat file CMS
Campaign Genius - Send dynamic email content through any platform, instantly.
Volleyy - Easiest tool to create responsive newsletters.
Mailmeteor - Send hundreds of personalized emails with Gmail.