FlowMapp - FlowMapp is a UX planning tool for creating visual sitemaps and user flow.
Mailivery - Reach the Inbox, not the spam folder.
Octopus.do - Build your website structure in real-time and rapidly share it to collaborate with your team or clients. Start prototyping websites or apps instantly.
Sidemail - The simplest way to send transactional emails. Sidemail makes sending transactional emails trivial, it's perfect for side projects, MVPs or the next big thing.
DYNO Mapper - Create Sitemaps with the DYNO Mapper Visual Sitemap Generator.
Postal - Open source mail delivery platform, alternative to Mailgun or Sendgrid