It has been quite some time since we first announced Unibox, a completely new approach to email on the Mac. We got a lot of great feedback and we think we owe you some more information.

What is the current state of development?
We are making good progress and have used development versions of Unibox internally for quite some time. Although there is still a lot of work to do, Unibox is already a fully featured mail client.

Will Unibox support multiple accounts?
Yes, the current version is already syncing with all our private and work accounts, including Gmail, iCloud and self-hosted IMAP servers.

Which version of OS X will be required?
Unibox will run on Mountain Lion and integrate with all core OS X technologies like Notification Center, Spotlight and Quicklook.

Will there be a beta?
Yes, a private beta will start early next year. Unibox is already in a good shape, but we want to resolve all major issues, including UI polishing and performance improvements, before putting it into the hands of beta testers. We will announce the beta phase via our newsletter. Subscribe now to get notified:

Features
Some of the key features of Unibox (contact-based, chat-style UI, Finder-like attachments interface) have already been mentioned on macrumors. We will cover all of the unique features in detail in a series of upcoming blog posts, starting with the single-window mode for writing emails (screenshot below) in the next post.

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