KanbanMail takes your inbox from a confusing mess and turns it into a clear action plan!
KanbanMail has gone through lots of improvements and optimizations throughout the last year. If you are looking for a way to optimize your email workflow, you should give it go.
Sortd - Rated the #1 App for Gmail
HEY - Email at its best, new from Basecamp.
Drag for Gmail - Transform Gmail into organized To Do lists (like Trello)
Horde - Horde Groupware is a free, enterprise ready, browser based collaboration suite.
Flow-e - Turn your Gmail or Office365 inbox to a Visual Task Board.
InstAddr - Disposable email address application.