1B Mail: Email & IMAP Client

Content rating
Everyone
5+
Downloads
Content rating
Everyone
Users Interact
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About this app

1B Mail is an email app for Android by 1Byte Systems: every account in one inbox, real conversations and private reading. It connects directly to your own mail servers. There are no 1Byte servers in between, no ads, no analytics and no tracking.

ALL YOUR ACCOUNTS, ONE INBOX
• A unified inbox for every account, or each account with its own folders
• Works with any IMAP/SMTP account: your work address, your own domain, IONOS, Gmail (with an app password) and many other providers
• Type your address: 1B Mail finds the server settings and tests the connection
• Focused and Other: newsletters and notifications are sorted out with local rules on your phone
• Each account in its own colour, with Favorites and Flagged close at hand

REAL CONVERSATIONS
• Replies are grouped into one conversation, even across folders: your answer from Sent sits next to the message it answers
• Swipe to archive or delete, with Undo. Choose what each direction does: Archive, Delete, Read/unread, Flag or Nothing
• Write with formatting, attachments, signatures and an identity per account; reply, reply all and forward
• Undo send for a few seconds after you tap Send; drafts are saved as you type
• Works offline: changes are sent when you are back online
• Opens mailto: links and files shared from other apps

FAST SEARCH ON YOUR PHONE
• Search every account at once, with filters for account, sender, attachments, unread and flagged. The index stays on your device

READ WITHOUT BEING WATCHED
• Remote images and tracking pixels are blocked until you allow them: show them once, or trust a sender
• Messages are cleaned up before they are shown and scripts never run
• A warning when the text of a link does not match where it really goes

NOTIFICATIONS YOUR WAY
• One notification per account, for Focused mail or for all new mail, with Archive, Reply and Mark as read right in the notification
• Easy on the battery: by default new mail is checked every 15, 30 or 60 minutes
• Optional Instant mail (off by default) keeps a live connection to your mail servers so new mail arrives within seconds, with a permanent notification while it is on

PHONE, FOLDABLE AND TABLET
• On an unfolded foldable, the message list and the conversation sit side by side; folding keeps your place
• On tablets: folders, list and reading pane at once
• Light and dark theme, normal or compact rows, text up to 200 % and TalkBack support

BRING YOUR ACCOUNTS FROM YOUR COMPUTER
Already use 1B Mail on Windows or Linux? Scan the QR code it shows and your accounts arrive over your local network, end-to-end encrypted, with no server in between. Passwords only travel if you choose to send them. An exported .1bmail file works too.

PRIVATE BY DESIGN
• No account with us needed and no servers of ours in between: your mail travels encrypted between your phone and your mail servers
• Passwords are kept in an encrypted vault protected by the Android Keystore. They never leave this phone and are not included in backups
• No ads, no analytics, no crash reports sent anywhere
• Strict TLS; a certificate exception only after you see and confirm its fingerprint

GOOD TO KNOW
• IMAP only: POP3 is not supported. No calendar or contacts yet
• Gmail connects with an app password, and the app guides you through creating one
• Hotmail and Microsoft 365 accounts sign in with Microsoft; a work account may need your administrator's approval first

Available in 21 languages. Questions and ideas: 1bytesystems@gmail.com
All your email accounts in one inbox. Conversations, trackers blocked, no ads
Updated on
Nov 1, 2026

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
  • No data shared with third parties
    Learn more about how developers declare sharing
  • This app may collect these data types
    Device or other IDs
  • Data is encrypted in transit
  • You can request that data be deleted

What’s new

1B Mail 0.2.7:
• Hotmail, Outlook.com and Microsoft 365: work and school accounts are recognised and go straight to Microsoft sign-in
• Clearer sign-in errors, with a note for your IT admin if your organisation blocks access
• More reliable return from the browser after signing in, also on foldables
• Fewer Google components: Play Billing no longer includes its logging library