Online storage company Dropbox has acquired popular email client Mailbox for an undisclosed fee - just a month after it launched on the iOS App Store.

Dropbox
Dropbox

Mailbox gained widespread praise for its slick and attractive user interface when it launched in February, despite forcing users to join a queue of more than 300,000 fellow early adopters, a queue that was processed by just 14 employees of parent company Orchestra. All those customers will now head to Dropbox.

Dropbox CEO Drew Houston said on the company blog: "Like many of you, when we discovered Mailbox we fell in love - it was simple, delightful, and beautifully engineered. After spending some time with [Mailbox CEO] Gentry Scott, and the team, it became clear that their calling was the same as ours at Dropbox - to solve life's hidden problems and reimagine the things we do every day.

"Together we could save millions of people a lot of pain. We're all looking forward to making Mailbox even better and getting it into as many people's hands as possible. There's so much to do and we're excited to get started."

Still processing a queue of new users, rather than letting them all join at once and potentially flooding its servers and causing instability, Mailbox said it had 1.3 million reservations and its servers were processing more than 60 million emails every day.

On the Mailbox blog, it said of Dropbox: "They're a profoundly talented bunch who build great tools that make work frictionless, and Mailbox fits Dropbox's mission like a glove. They've got a ton of experience scaling services and are experts at handling people's data with care. Dropbox is our kind of company."

The price Dropbox paid for Mailbox has not been announced. All that is known about Mailbox's finances is that it has $5.3m (£3.5m) in venture capital behind it.

IBTimes UK registered for a Mailbox account this week and found that almost 529,000 people were queued in front of us with 100 more joining the back of the queue every minute.