Aster Mail: Encrypted Email

Aster Communications Inc. | Email

9 Downloads 17 Views v0.6 19.68 MB 4.1+

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(19.68 MB)

Editor's Overview

Aster Mail: Encrypted Email is a email application developed by Aster Communications Inc., packaged as a single Android APK of version 0.6 weighing in at 19.68 MB. The package targets Android 4.1+ and above. Below you'll find the publisher's own description, a quick spec sheet, and a short buyer-beware checklist so you know exactly what you're installing before tapping download.

Install Checklist

Only download through the button on this page — never from third-party mirrors or shortened links, which are the most common way malware spreads.
File size is a light 19.68 MB, so it installs quickly even on modest connections.
This build is signed by "Aster Communications Inc." — always verify the developer name matches what's listed on the app's official store page before installing an update.
After install, Android may prompt you to allow "Install from unknown sources" — approve only this one install, then revoke the permission in Settings > Apps > Special access.
We link directly to the APK file or the publisher's repository; we do not modify the binary. Always run a virus scan after any sideloaded install.

About this app

Aster Mail is a private, encrypted email app for astermail.org accounts.

Your messages are encrypted on your device before they leave it. The server stores ciphertext and nothing else, so nobody at Aster can read your mail, scan it, or sell what is in it. There are no ads, no trackers, and no analytics anywhere in the app.

Private by design
- End-to-end encryption between Aster users, using a post-quantum ratchet protocol
- Zero-access architecture: the server holds only encrypted content
- No ads, no tracking, no telemetry, no profiling
- Open source under AGPL-3.0, so anyone can audit what the app does

Email aliases
- Create an alias for each site you sign up for, and turn one off when it starts getting spam
- See which alias a message arrived on, right in the message list
- Import and export your aliases

Your own domain
- Send and receive on a custom domain, with DKIM signing handled for you
- Buy a domain from inside the app

Everyday mail
- Folders, labels, categories, and search across your whole mailbox
- Swipe actions and a toolbar you can customize
- Templates, signatures, scheduled send, and auto-forwarding
- Blocked senders, sender filters, and an allow list
- Encrypted offline storage, so your mail is there without a connection

Security
- Biometric lock
- Two-factor authentication and a recovery key
- Active session management, so you can sign out a device you no longer have

Notifications
- Private mode hides the sender and subject on your lock screen
- Quiet hours schedule when notifications arrive
- Per-folder muting

This F-Droid build contains no Firebase or Google Play Services dependencies. Push notifications are delivered through any UnifiedPush-compatible distributor, such as ntfy. Background polling takes over when no distributor is installed.

Aster Mail is free to use. Paid plans add storage, larger attachments, more aliases, and custom domains.

Source code: https://github.com/Aster-Privacy/Aster-Android

Details

Version	v0.6
Size	19.68 MB
Developer	Aster Communications Inc.
Category	Email
Package	org.astermail.android
Android	4.1+
Last Updated	Oct 29, 2026
Downloads	9

Frequently Asked Questions

Is Aster Mail: Encrypted Email free to download?
Yes. The APK file linked from this page is free. The developer may offer in-app purchases once installed, but obtaining the installer itself costs nothing.

What Android version does Aster Mail: Encrypted Email require?
Android 4.1+ or newer. Installing on older devices may cause crashes or refuse to install.

Is Aster Mail: Encrypted Email safe to install?
We link to the exact APK published by Aster Communications Inc.. We do not modify the file. Still, as with any sideloaded app, scan it with a reputable antivirus before opening it, and only grant permissions the app genuinely needs.

How do I update Aster Mail: Encrypted Email?
Install the newer version on top of the old one — Android will keep your data. If the signature differs, uninstall first (you may lose local progress).

Why is the app not installing?
Common causes: not enough storage, an older Android version than 4.1+, or a conflicting build already installed. Free up space, check your OS version, and uninstall any previous copy before retrying.

How to Download & Install Aster Mail: Encrypted Email

Tap the Download APK button above and save the file to your device.
Open your device Settings → Security (or Apps → Special access → Install unknown apps) and allow your file manager or browser to install unknown apps for this one file only.
Open the downloaded org.astermail.android.apk file from your Downloads folder.
Tap Install and wait for Android to finish.
Open «Aster Mail: Encrypted Email» by Aster Communications Inc. and grant only the permissions it actually needs.
Revoke the "unknown sources" permission once you are done installing.

Note: this page hosts or links to the installer only. The application name, icon and description are provided for identification. All trademarks belong to their respective owners.