By Glenn Fleishman

April 21, 2026 4:10 PM PT

MailMaven review: An email nerd’s best friend?

I don’t have a dog for the same reason it’s hard for me to get excited about email apps: the short, sweet lifespans make you love them so intensely and miss them forever when they’re gone. You’re never sure whether you’ll spend several years with a favorite pup or mail client, or get lucky and have 15 or more. Eventually, in my experience with dogs and email clients, they grow old, fade, and are no more. This is the cycle of life and the software business cycle for many apps.¹

While I love dogs and seek permission to pet from the owner of nearly every dog I encounter, I have gone cold on new email apps after decades of losing my greatest loves.

I can’t remember which horrible mainframe program I used first, in the 1980s, but pine—developed at nearby University of Washington—was a standby in my early Unix-plus-Internet days. I adopted Eudora as soon as I found it and used it for many, many years because it only offered text-based email—no HTML! When it petered out around 2002, Mailsmith arose from Bare Bones, with the same text-only front end. Despite friend Rich Siegel and other developers keeping it alive long after its commercial utility had ended, I eventually shifted to Postbox in 2019. Guess what happened in 2024.²

Thus did I approach the relatively newly released MailMaven version 1 with some fear, even as I smoothed its fur, patted its back, and said, “Good mail app! Good mail app!” I’m happy to say that MailMaven gave me the puppy experience: I’m so excited to meet it and get to know it, and I’ll be even more so as it calms down and matures, and I get to live alongside it for what I hope is a long time.

MailMaven can be a good pal to a casual user, someone who wants something better than a Web app, like Gmail, and might have multiple email accounts. It’s friendlier and easier in its default setup than Apple’s Mail—less frustrating and more customizable, but you don’t have to make any substantial tweaks to start using it.

For the true mail nerd, of which I number myself, MailMaven could become your best friend. It has a cornucopia of options that let you wrap MailMaven around your particular needs. And we’re only at version 1.0.

It’s here I should note that I have no financial interest in MailMaven’s success, but I did edit the Take Control of MailMaven book, written by publisher Joe Kissell, who has advised SmallCubed, the developer, and also wrote the regular user manual.³ This was in my paid capacity as executive editor at Take Control Books.

During the late development process and early 1.0 bug-fixing release schedule, I worked with the app quite a lot, reported a number of issues (which were fixed), and had planned to transition to MailMaven last fall. I wound up holding off—part of that was on me, and part on them. I’m glad I waited, because I can give the app a clean look after solving my problems and after the developers have given themselves a good shake and reached release 1.0.14.

Think outside the mailbox

MailMaven emerged, like V’ger in Star Trek: The Motion Picture, from what was originally SmallCubed’s MailSuite, a series of components to improve Apple’s Mail for macOS.⁴ When Apple changed its plug-in architecture, the folks at Small Cubed set out to build the mail client they were trying to tweak Mail to be.

You can tell! So many of the frustrations and non-configurable parts of Mail are easily dealt with in MailMaven. And they’ve added sophisticated rule-based processing and a host of other features that came over in part or in whole from their previous add-ons.

This isn’t a copy of Mail, though—neither for copyright nor look-and-feel purposes. MailMaven has its own nature, which I would describe as colorful. It’s not garish, but you wouldn’t accuse the developers of working with a bland palette. They use color as ably and extensively as they do interface design elements. You can change nearly everything related to color, so you’re not limited to the defaults. This is true in many ways throughout the interface.

Like nearly all email clients, MailMaven structures itself around accounts, mailboxes, messages, and threads. Since this is how you set up, store, and read email, that makes sense. By default, the accounts sidebar shows your email accounts, with mailboxes organized beneath each. With a mailbox selected, you see messages in the main view. It uses some elaborate arcs to show you the connections among threaded messages, a step up (if not a step too far for some potential users) than the bland or hard-to-follow threading in many other apps.

From there, however, I feel like we move into new territory. That account/mailbox view is just one option. The sidebar has four others:

• Favorites: You can favorite an account or individual mailboxes. You can then rename the entry within favorites without renaming the account or mailbox!
• Smart Mailboxes: Familiar from Mail and many other kinds of apps, smart mailboxes show the results of search criteria you set up.

• Tag Mailboxes: Perhaps unique to MailMaven, you can apply tags in many kinds of ways, and then show matches. It’s like a subcategory of a smart mailbox, but one derived from how you have tagged messages. (You can also skip this entirely.)
• Review Mailboxes: This, to me, is a winning feature if it fits how you work. It’s kind of the ultimate way to mark messages you don’t want to file but don’t want clogging up your inbox. You can mark a message as something you want to review tomorrow, on a particular date, or that you expect a reply to, among other variants.

Tags deserve even more explanation, even though I haven’t started using them yet! A number of non-email apps offer forms of tagging that let you cut across other kinds of organization. MailMaven might have the most sophisticated version available. Tags aren’t just metadata—they’re almost supradata? Data that sits above metadata as an organizational scheme.

Without turning this review into a book, I’ll note three important aspects about tags:

• You can set them manually.
• Tags can be keywords, projects (another grouping mechanism), an importance ranking (lowest to highest, 1 to 5), a review date, a background color (see above), freeform notes, an alternative subject line that overrides the original subject, or flag icons.
• They can be used in rules and set by rules. So you can have a rule that says, “Every time I send email to unsubscribe—check the email address, the contents of the message, and so on—tag this message with the ‘unsubscribed’ keyword.” Or, “Every message that has the text ‘Six Colors’ in it should be tagged as high importance, assigned to my ‘Six Colors’ project [another grouping mechanism!], and marked for review.”

Note just above that I mentioned a rule for your outbox: that’s right—you can trigger rules before and after sending messages. You can write a rule that prompts you to make sure you attached a file promised in the email! Or ones that file outgone messages in folders corresponding the topics you file inbound ones—or that delete certain messages after sending.

You can see that MailMaven has a lot of automation, processing, grouping, and review concepts at its heart. I would argue that if none of that sounds appealing, like you had an “oh, thank goodness!” reaction to the above, I’m not sure MailMaven’s general functionality will overwhelm you enough compared to email apps already out on the market—not Mail, particularly, but others.

However, you might still give it a spin just because it’s fun and easy to use.

My smart path to becoming a maven on mail

Apparently, I have 700,000 stored emails. Do I need all these? Certainly not. Am I going to spend a sizable amount of time pruning these by hand? Can an algorithm help? It already did, dropping 100,000s of duplicates and old automated messages of no value.

When I first attempted to switchover to MailMaven, I was stymied. I don’t need that much email actively online, but I don’t want to lose access to it or the ability to search my archives. MailMaven offers effective import options, so it wasn’t hard to start importing mailboxes. The app can import the standard mbox format, as well as individual email messages in the also standard eml and emlx formats. But it looked like we might be talking several days, if not weeks, of uninterrupted import action. Seemed apt to fail due to entropy, and then I’d have to figure out what was left to do.

So I put this off for a while.⁵ A couple of weeks ago, I strategized: what if I dumped old email into a searchable database that wasn’t part of an email app? With a little heavy lifting, I imported everything, with a lot of parsing, from the early 1990s to the present.⁶ I have this database update nightly with the last 24 hours of filed email.

I then trimmed the email to import into MailMaven to just a year’s worth and imported only the folder structure from that period—about 18,000 emails—which was ready to go in minutes. MailMaven can’t import folders and mailboxes, but it can import the contents of multiple mailboxes at once. I re-created folders, then imported the mailboxes for them.⁷

Because I’d either used a series of modestly featured email apps or I’d used a modicum of features in more heavily built-out programs, the rest of my migration involved just two things:

• Replicating a filtering rule, so that sales receipts from book sales don’t clog my inbox, but are properly filed. That took a minute or so.
• Figuring out which favorites I wanted to put in the Favorites sidebar. That took longer.

With only a few dozen mailboxes organized thematically, I quickly figured out which dozen or so I had manually filed emails into. I am absolutely sure I could make better use over time of keystrokes and keystroke rules. The former requires learning and training my muscle memory; the latter means figuring out what I do repetitively, writing a rule, and then assigning a keystroke. Am I reading an email from Jason Snell, then always filing it in my Six Colors mailbox? I could assign a keystroke! Rules can be just as complex as those for incoming and outgoing email.

Yo, dog, what’s the bottom line?

I like MailMaven quite a lot. And each day I use it, I tweak something that makes me like it more. The developers fixed a synchronization bug that seemed entirely to affect my workflow just after I installed 1.0.12. They suggested I get on the beta track—which you can enable in the app—and the next release, 1.0.13, solved the problem. (In brief: I read email on two Macs, but only filed on one. An automated rule, mentioned above, redirects book receipts. However, it failed to mark messages as synchronized, so my “reading” Mac removed them from its inbox after retrieval. Receipts would still pile up even though they had already been deleted from the server inbox. It works great now.)

SmallCubed offers MailMaven for a flat fee of $75 for perpetual use of the version you purchase, including a year of updates and tech support. After a year, you can pay $75 (at current pricing) to renew the license to receive further updates and support, or you can continue indefinitely to use the latest version included in your original year of updates.

Is $75 a year too much? (Or $75 for the first year, and then when you are annoyed enough to pay for another year?) Given how much I use email, and how much of an improvement MailMaven is over Mail, not to me.⁸ You can try MailMaven free for 15 days.

The bigger question is the issue I mentioned at the outset. How long will MailMaven abide? It’s a small, scrappy company that persisted past Apple pulling the rug out from under plug-ins. It’s not a startup, and they invested years to get to this point.

But the market is cruel. Will it MailMaven around in six months, a year, five years—dare I hope for 10 or 20? Having developed a better pathway for migration for my archives, it might be that I have to think of MailMaven as a foster dog, rather than me providing a forever home.

Nonetheless, I open my heart as I do to all household animals, and recommend MailMaven as something you try to see if it fits you now, and hope that it grows with us all.

[Glenn Fleishman is a printing and comics historian, Jeopardy champion, and serial Kickstarterer. His latest book, which you can pre-order, is Flong Time, No See. Recent books are Six Centuries of Type & Printing and How Comics Are Made.]

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