I've tested so many Linux email clients - why I'm recommending Aerion above all else

For years, Geary has been my go-to email client. It's lightweight, simple, and sports a modern GUI. However, it's not without its quirks.

When using Geary with a tiling window manager, the GUI doesn't always behave as expected, and launching the app on Pop!_OS can be a bit finicky. So, when I heard about Aerion, a new, cross-platform email client available for Linux, MacOS, and Windows, I had to give it a try. This open-source app is Linux-first, privacy-focused, lightweight, and efficient.

The GUI is well laid out, making it easy for anyone to jump in and start using the app right away, with no learning curve. Aerion is sponsored by 3DF, a Hong Kong-based IT consultancy. For those concerned about the trustworthiness of 3DF and Aerion, the source code for the email app is available in the official GitHub repository.

Aerion's feature list is impressive, supporting email accounts such as Gmail, Outlook/Hotmail, Yahoo Mail, iCloud Mail, ProtonMail Bridge, Fastmail, Zoho Mail, AOL Mail, GMX Mail, Mail.com, and IMAP/POP. It also includes rich-text message formatting, theming, in-window or detached-window composing, read receipts, remote image loading enable/disable, signatures, contacts, email archiving, a spam filter, focus mode, email filtering, tracking element removal, and more. The best part of Aerion, for me, is its UI.

It's modern enough to look right at home on any OS, with an account pane, an email list pane, and a viewing pane. The app also features Focus Mode, which switches the UI so that you only see the currently viewed email. To enable Focus Mode, simply click the small square to the left of the printer icon near the top right.

Aerion may still be in pre-release, but I found it remarkably stable. To install Aerion on MacOS and Windows, grab the necessary installers from the official download page. On Linux, Aerion is installed via Flathub, using the command: flatpak install --user io.github.hkdb.Aerion.

Overall, Aerion's clean, modern UI and range of useful features make it a top pick for Linux users looking for a reliable and efficient email client.