Yes, it’s possible to achieve the elusive serenity of “inbox zero” with a new iPhone app called Mailbox.

Mailbox does something nothing else has done before: allow emails to be “delayed” for future delivery when you have time to deal with it. And it executes this function with a gorgeous interface that allows for very quick email parsing.

Watch our video review:

The gestures are simple: slide the email to the right to archive a message and remove it from the inbox. Slide it all the way to the right of the screen and an “x” will appear indicating that the email will be deleted. If you change your mind, simply shake the iPhone and a dialog box will pop up to undo the action.

Sliding the email slightly to the left is when Mailbox App really begins to shine.  The gesture will bring up a set of options such as “later today,” “this evening,” “tomorrow,” and “this weekend.”  Tapping on one of those will remove the email from the inbox and have it redelivered at a later time. You have the option to define exactly what time is associated with those options, or define a specific redelivery time. A long swipe to the left will allow the email to be assigned to a list which associates with a custom tag inside Gmail.

The app functions well with its web based counterpart, Gmail. Delayed messages are moved to a gmail folder called “later” and can be accessed from the Gmail web client or any compatible email application. Additionally Mailbox has an option to review delayed email messages and their delivery times inside the app.

So far the app is only available on the iPhone and iPod Touch and requires a Gmail account. It doesn’t work with other email services.

Mailbox has become very popular very quickly. So popular that a virtual line has formed to get into the app and it may take several weeks before you’re able to use it. After installing, Mailbox will report your place in line and how many others are ahead of you. My wait was approximately two weeks.

All of this success did not go unnoticed. Shortly after the Mailbox team activated its millionth user, they were acquired by popular file syncing app Dropbox.

Connect with Lon: