Varolio

I'm obsessed with productivity apps, even though many of them end up being more of a waste of time than a time saver. Varolio is an exception.
The app's tagging feature is fantastic. It automatically sorts incoming emails into categories like 'Work', 'Personal', 'Urgent', etc – you can create any tag that works for you.. This isn't just based on keywords, but thanks to AI the app seems to understand context - It's like having a little virtual assistant who organises your inbox while you dedicate time to more useful tasks.
The app can write replies instantly based on the email content. For example, it can send a polite 'I'll get back to you soon' message if it detects a question or a request.
The interface is simple and easy to use. You can start using it right away without needing a manual.
I hope it comes back to Appsumo, so I can upgrade to a higher tier.