Flow-e is a visualization layer on top of your Gmail or Outlook inbox. It provides an elegant Kanban-like workflow that's combined with the ideas behind Inbox Zero and GTD. Flow-e eliminates the need of external task management tools and transforms your inbox into a central To Do app.
Sortd - Rated the #1 App for Gmail
Mobbin - Latest mobile design patterns & elements library
Drag for Gmail - Transform Gmail into organized To Do lists (like Trello)
pttrns - iPhone and iPad user interface patterns
KanbanMail - A Kanban board for your emails.
Page Flows - User flow design inspiration for mobile & desktop