Unibox is a free iPhone app developed by eightloops GmbH that aims to simplify email management by grouping your emails by sender. With Unibox, you can easily navigate through your emails and keep your inbox organized.

The main feature of Unibox is its ability to group emails by sender. This means that with just a single tap, you can see all the messages and attachments you have exchanged with a specific person in one place. This makes it incredibly convenient to find and reference past conversations or attachments.

Another useful feature of Unibox is its swipe functionality. With a simple swipe, you can quickly get rid of dozens of newsletters and notifications from the same sender that you no longer need. This helps to keep your inbox clutter-free and ensures that you only see the emails that are important to you.

Unibox is compatible with all email providers that support the IMAP protocol, including popular services like Gmail, Hotmail, Outlook.com, Yahoo, and Office365. It also works with self-hosted servers and other email providers that have IMAP enabled.

If you're looking for a simple and efficient way to manage your emails, Unibox is worth considering. It's available for free on the iPhone and also has a version available for Mac, allowing you to seamlessly manage your emails across multiple devices.