From the June 2013 issue of Entrepreneur

"If e-mail was the original online game-changer, it hasn't changed much since," says Gentry Underwood, co-founder and CEO of Mailbox, an app for iOS. "It was remarkable at the time, but it wasn't designed for a world where we're carrying e-mail around in our pockets," he says.

Mailbox, recently acquired by cloud-based file-hosting service Dropbox, enables users to quickly and easily manage their inboxes on the go. Using simple swipes, readers can archive a message, delete it, move it to a folder or--this is the cool part--schedule it to reappear an hour, a day or a week later.

Get the message: Gentry Underwood of Mailbox.
Get the message: Gentry Underwood of Mailbox.
Photography by Thayer Allyson Gowdy

A short swipe to the right archives an e-mail. A longer swipe deletes it. A short swipe to the left reassigns a message to appear when there is time to deal with it. Ideally, what are left over are the messages that matter most--or, even better, an empty inbox.

Granted, those already vigilant about clearing out their mail won't see anything new here, but those who are overwhelmed by a nightmare of unanswered messages each day should appreciate the app's simple, touch-based approach to prioritizing their inboxes.

While currently free of charge from the iTunes App Store, Mailbox works only with the iPhone and Gmail; the company plans to roll out versions to support other e-mail services and operating systems, such as Outlook and Android devices, in the near future. Then, everyone will be able appreciate Underwood's maxim: "Happiness is an empty inbox."