Penguin Mail

Penguin Mail keeps several Gmail accounts in sync from the system tray,
shows them in one inbox or one at a time, and keeps your mail on your own
computer. It talks to Google directly, so no other server sees your
mail.

- One inbox for every account, with Gmail's categories, labels and search
- A composer that shows formatting as you write, with Undo Send and Send Later
- Flags in seven colors, VIPs, smart mailboxes and reminders
- Gmail's rules, automatic replies and plus addresses, changed from the app
- OpenPGP and S/MIME signing and encryption through your own GnuPG
- Remote images blocked until you ask for them
- An assistant that runs on a local model or on Claude, off until you pick one

Adding a Gmail account takes one sign-in with Google in your browser.