Connect mailboxes
Providers, app passwords, OAuth, and what the sync keeps in step with your mail server.
Providers
Every provider connects over IMAP (to read) and SMTP (to send) with your address and an app password, not your account password. The servers of the known providers are built in.
| Provider | How to get the app password | OAuth |
|---|---|---|
| Gmail | Turn on 2-Step Verification, then create an app password under Google Account › Security › App passwords. | Yes, when the server has a Google client |
| Outlook | Create an app password under Microsoft account › Security › Advanced security options. Some Microsoft 365 organizations turn IMAP sign-in off. | Yes, when the server has a Microsoft client |
| Yahoo | Create an app password under Yahoo Account Security › Generate app password. | Pending provider approval |
| iCloud | Create an app-specific password at account.apple.com › Sign-In and Security. | No |
| Lark | In Lark Mail, open Settings › Third-party email client, turn on IMAP/SMTP and generate a password for this device. | No |
| Zoho | Turn on IMAP access in Zoho Mail settings, then create an app password under Zoho Accounts › Security › App passwords. Custom-domain or non-US accounts: use IMAP with the servers shown in Zoho Mail settings. | Yes, when the server has a Zoho client |
| IMAP | Use the IMAP server and port your provider documents. The connection always uses TLS. | No |
Connecting signs in first: a wrong password or a server that refuses IMAP is reported before anything is saved.
Where your credentials live
App passwords and OAuth tokens are encrypted in the database with a key derived from the server's APP_SECRET. They are never shown again after you save them.
What the sync does
- First sync: the newest 50 messages of each folder: Inbox, Archive, Drafts, Sent, Spam and Trash.
- After that: everything new, on every run. The hosted app syncs every 5 minutes; a self-hosted server sets
MAIL_SYNC_INTERVAL. Sync now on the account card runs one right away. - Sorting: new inbox mail is classified by the organization's model (see AI features).
- Write-back: reading, starring, moving and deleting in the app is written back to the mail server, so your phone's mail app sees the same state.
Read and starred states come from the server when a message is first synced. Gmail archives into All Mail, which is not synced, so archived Gmail mail leaves the app.
When a sync fails
The account card shows when it last synced and why the last sync failed, if it did; the mail list shows the error too. A changed or revoked app password is the usual cause: disconnect the account and connect it again with a new one.
Disconnecting
Disconnect removes the account and the mail synced from it. Nothing is deleted on your mail server.