Mailbox allows you to easily postpone, categorize or archive emails. It's still in beta and has some quirky bugs, but despite the little annoyances, I have literally become 30% more productive since I started using this.
Co-founder & CEO - sli.do
1%Stacklist Startups Are Using Mailbox
Mailbox has redesigned the inbox to make email light, fast, and mobile-friendly. Quickly swipe messages to your archive or trash and scan entire conversations in a chat-like view. Now available for iPhone/iPad, Android, Gmail/iCloud and Desktop.
Visit the website: https://www.mailboxapp.com/