Everyday

Mail

Read your email next to your tasks, including Proton Mail through Proton Mail Bridge.

What Mail does today

Mail shows your inbox inside Marbler. You can read it on every device you use.

Right now Mail only reads. It can't send or reply yet. Sending is coming.

Marbler checks each account about every 2 minutes. It keeps a copy of the last 90 days of each inbox. Older messages drop off on their own.

Add an email account

Gmail and Google email

Gmail connects with an app password: a separate 16-letter password Google makes just for Marbler. Your normal Google password stays private.

Open Settings, pick Mail, tap Add an account and pick Google.
Turn on 2-Step Verification in your Google account. The Open Google security button takes you there.
Make an app password and name it "Marbler". The Make an app password button takes you there.
Copy the 16 letters Google shows and paste them into App password. Spaces don't matter.
Fill in your Email address and tap Connect.

Labels, stars, archive and your Sent mail work as before.

If Google says no:

"Gmail didn't let Marbler in with that password": paste the app password (16 letters), not your normal Google password; check the Gmail address is spelled right; still stuck, make a new app password and paste it again.
"Your Google account doesn't allow app passwords": work and school accounts often block them. Ask your admin.

If Gmail was added with Sign in with Google before and stops working, its row says Reconnect Gmail with an app password. Tap it and follow the same steps. Your emails and folders stay.

Outlook and Hotmail

Open Settings and pick Mail.
Tap Sign in with Microsoft (Outlook) for Outlook, Hotmail, Live and Microsoft 365.
Sign in on Microsoft's own page and allow Marbler to read your mail.

If you don't see this button, the server isn't set up for it yet, and adding these accounts is coming soon.

Yahoo Mail and iCloud Mail

Adding these is coming soon.

Any other email

For your own domain, or any other mail service that uses IMAP:

Open Settings and pick Mail.
Tap Other email.
Fill in Email address. Marbler copies it into User name for you.
Fill in Mail server (IMAP) and Port. Your mail provider lists these. They are often called "IMAP settings".
Pick Security. SSL/TLS uses port 993. STARTTLS uses port 143. Picking one changes the port for you.
Fill in Password.
Tap Test connection. When it says "It works", tap Add account.

On a computer, Mail is on the left bar. On a phone, it is under More.

Proton Mail

Proton Mail keeps your mail encrypted, so normal mail apps can't read it directly. Proton gives you a free helper app, Proton Mail Bridge, that fixes this. Bridge runs on a computer. It unlocks your mail on that computer and hands it to mail apps there.

Bridge only talks to the computer it runs on. That shapes how you connect it. There are two ways.

Option 1: the Marbler desktop app and Bridge on the same computer. Easiest. Mail arrives while that computer is on.
Option 2 (recommended for all-day mail): Bridge and Marbler's mail sender on an always-on computer or home server. The mail sender is a small program that runs next to Bridge and sends your mail to Marbler. Mail keeps arriving all day and night, and nothing is opened to the internet. See Proton Mail on Marbler, step by step.

First, set up Bridge

You need this for both options.

Download Proton Mail Bridge from Proton's website and install it.
Open Bridge and sign in with your Proton account.
Wait for Bridge to finish syncing your mail. The first time can take a while.
In Bridge, click your account. Bridge shows a username and a password for mail apps.
Copy both. This password is made by Bridge. It is not your Proton password. Never type your Proton password into Marbler.

Bridge uses port 1143 for reading mail and 1025 for sending.

Option 1: desktop app on the same computer

Install the Marbler desktop app on the computer that runs Bridge, and sign in.
Make sure Bridge is open and signed in.
In Marbler, open Settings and pick Mail.
Tap Proton Mail (Bridge on this computer). Marbler looks for Bridge and says when it finds it.
Paste the Bridge username into Bridge user name and the Bridge password into Bridge password.
Leave Port at 1143 unless you changed it in Bridge.
Tap Add account.

Your mail now shows in Marbler on your phone and on the web too.

New mail only comes in while that computer is on, awake, and running Bridge and Marbler.
When the computer is off, nothing new arrives. When you turn it back on, Marbler catches up on everything you missed.

Option 2: an always-on computer or home server

Pick this if you want mail on your phone even when your main computer is off. You need a computer that stays on all the time, such as a home server, with Bridge running on it.

The easiest way is Marbler's mail sender next to Bridge: tap Connect a mail sender in Settings › Mail for its token, then follow Proton Mail on Marbler, step by step. It works with marbler.app and with your own server, and Bridge stays on its own private network.

If you run your own Marbler server, it can also connect to Bridge directly, without the mail sender:

If you run your own Marbler server on the same machine or the same home network as Bridge:

In Bridge, open Settings, then Advanced settings, and look at Connection mode. It says STARTTLS or SSL.
In Marbler, open Settings › Mail › Other email.
Put the Bridge username in Email address and User name.
For Mail server (IMAP), use 127.0.0.1 if Marbler runs on the same machine. Otherwise use that machine's address on your network.
Set Security to match Bridge (STARTTLS or SSL/TLS). Then set Port to 1143.
Paste the Bridge password into Password.
Tap Test connection. The first time, Marbler says it doesn't know the server's certificate and shows its fingerprint. See Trust Bridge's certificate.
When it says "It works", tap Add account.

Your Marbler server only connects to addresses inside your own network if you allow them. Add the Bridge machine's address to MARBLER_MAIL_ALLOW_HOSTS in your server settings.

If you use Marbler at marbler.app, Marbler's server is on the internet and can't see a computer inside your home. Use the mail sender: it sends your mail out to Marbler, so Bridge never has to be reachable from the internet. Never open Bridge to the internet yourself. Anyone who finds that address could try to log in to your mail.

Trust Bridge's certificate

Bridge locks its connection with its own certificate. No public authority signed it, so Marbler doesn't trust it at first. This keeps you safe from a fake server.

Tap Test connection. Marbler shows the certificate's fingerprint, a long string of letters and numbers.
To be sure it is your Bridge, open Bridge, go to Advanced settings, and use Export TLS certificates. Compare the fingerprint of that certificate with the one Marbler shows. They must match.
Tap Trust this certificate. Marbler tries again.

Marbler trusts only that one certificate, for that one account. If the certificate ever changes, Marbler stops before sending your password and tells you. Only trust a new one if you know why it changed, for example you reinstalled Bridge.

Privacy

Proton encrypts your mail end to end. Once Marbler copies a message, that copy is not end-to-end encrypted the way it is inside Proton. It is stored on your Marbler server and on your devices, like the rest of your Marbler data.
Your mail password is sealed on the server and is never sent back to any device.
Marbler keeps a copy of the last 90 days of mail per account. Older messages are deleted from Marbler, not from your mailbox.
Remove an account any time with Remove in Settings › Mail.

When it doesn't work

"The mail server didn't accept that user name and password": for Proton, use the password from Bridge, not your Proton password.
"The secure connection to the mail server failed": check the Port and Security match. For Bridge, use port 1143 and the same mode as Bridge's Connection mode.
"The mail server's certificate isn't signed by a known authority": this is normal for Bridge. Follow Trust Bridge's certificate.
"The mail server's certificate has changed since you trusted it": Bridge made a new certificate. Check it, remove the account, and add it again.
No new mail: make sure the computer running Bridge is on and Bridge is running. Tap Check now in Settings › Mail. With a mail sender, look at its log: it says what it is waiting for.