Google Design Sprint Kit - Your resource for planning and running a Design Sprint
Landingfolio - The best landing page designs for your inspiration.
FlowMapp - FlowMapp is a UX planning tool for creating visual sitemaps and user flow.
Landing Pages in MailChimp - Easy to build, custom landing pages for free
StdLib - Discover pre-built APIs, compose your own and build apps
SaaS Landing Page - The best SaaS landing page examples for design inspiration.