Aerion (Portable)

Aerion (Portable) is an open-source email client for Windows, listed in MirrorNest’s communication category. It is a standalone, lightweight application inspired by Geary and designed to use minimal CPU, RAM, and battery resources. It is intended for users who want to manage personal or work email without relying on GNOME Online Accounts or other system services.

The client supports multiple accounts through generic IMAP and SMTP, Gmail, Microsoft 365 and Outlook, Yahoo, Proton Mail through Proton Bridge, iCloud Mail, and GMX Mail. Fastmail, Zoho Mail, AOL Mail, and Mail.com are also listed as providers that have not yet been tested. A unified inbox can combine messages from different accounts while using color coding to distinguish them, and conversation threads group related messages. Basic local and IMAP search provides a way to find messages across the supported mail sources.

Aerion includes a detachable WYSIWYG composer and WYSIWYG signatures based on the TipTap editor. It can synchronize contacts through CardDAV, Google, and Microsoft services for autocomplete, and it provides basic removal of tracking elements from email content. Notifications can bring an email into focus when selected, while automatic synchronization resumes when the system wakes from suspend. The interface supports dark mode, multiple color themes, full keyboard navigation, vim-style shortcuts, PGP, and S/MIME.

As a portable Windows application, Aerion fits users who want an email tool that remains separate from broader system account services. MirrorNest links directly to the official Aerion release rather than mirroring the software. Its open-source license allows the product to be distributed in this direct-release model while remaining part of MirrorNest’s Windows communication catalog.