full mailboxThe last time I wrote about email startup OtherInbox, I was concerned that the service might feel a little redundant following the launch of Gmail’s Priority Inbox. Today, however, the Austin startup announced a new feature that could help it feel like an essential addition to the Priority Inbox, rather than a competitive product — which is what OtherInbox has been saying all along.

The new feature is called “unsubscribe”, and uh, you can probably guess what it does. Users may have subscribed to a newsletter and then stopped caring, or the newsletter company may have auto-subscribed their email address. (Since my VentureBeat email address is publicly available, I’ve been auto-subscribed to a whole bunch of newsletters that I don’t care about at all.) Either way, unsubscribing is often a pain. So services like the Gmail Priority Inbox and Other Inbox’s own Organizer already try to help users avoid irrelevant newsletters by shuffling them into a separate part of their inbox. In the case of Organizer, users can get a daily email digest summarizing what they missed in their “other inbox”.

The new unsubscribe feature takes things a step further — it’s not just hiding those news letters but eliminating them altogether. It was developed in partnership with email marketing compliance company LashBack. Here’s how OtherInbox says it should work:

Pedro uses Organizer to organize and prioritize his emails in Yahoo or Gmail. He reads about a new Organizer feature that makes it easy to unsubscribe from email lists. All he has to do is add the label “OIB/Unsubscribe” and Organizer takes care of the rest. He is intrigued and logs into his email and finds a newsletter to label. The next day, he might notice a new daily email from the same merchant is in the folder now. Any further emails from that merchant will now go directly into the new folder. Pedro will get a notice of his unsubscribe activity in his Organizer Daily Digest. In the background, we work with LashBack to remove the addy. Viola! Pedro has been removed from the list. He will notice the emails stop and the folder will be empty.

OtherInbox has raised a total of $4 million.