Frequently Asked Questions

What is Delta Chat?

Delta Chat is a new chat app that sends messages via e-mails, encrypted if possible, with Autocrypt. You do not have to sign up anywhere, just use your existing e-mail account with Delta Chat.

How can I find people to chat with?

With Delta Chat, you can write to every existing e-mail address - even if the recipient is not using the Delta Chat app. No need for the recipient to install the same app as yours, as with other messengers.

What are the advantages of Delta Chat compared to other messengers?

Which messages do appear in Delta Chat?

Delta Chat automatically shows:

Other messages do not appear automatically, and are to be found in Contact requests. If desired a chat can be started from there.

What about spam?

Does Delta Chat support images, videos and other attachments?

Who sees my profile picture?

Does Delta Chat support HTML e-mails?

Why do I have to enter my E-Mail password into Delta Chat? Is this secure?

As with other E-Mail programs like Thunderbird, K9-Mail, or Outlook, the program needs the password so you can use it to send mails. Of course, the password is stored only on your device. The password is only transmitted to your E-Mail provider (when you login), which has access to your mails anyway.

If you use an E-Mail provider with OAuth2 support like gmail.com or yandex.ru, there is no need to store your password on the device. In this case, only an access token is used.

As Delta Chat is Open Source, you can check the Source Code if you want to verify that your credentials are handled securely. We are happy about feedback which makes the app more secure for all of our users.

Which permissions does Delta Chat need?

Depending on the operating system in use, you may be asked to grant permissions to the app. This is what Delta Chat does with these permissions:

Groups

Creation of a group

Add members to a group

What is a verified group? Why is it experimental?

I have deleted myself by accident.

I do not want to receive the messages of a group any longer.

What do double ticks mean in group messages? Has everyone read my message now?

Encryption

Does Delta Chat support end-to-end-encryption?

What do I have to do to activate the end-to-end-encryption?

If end-to-end-encryption is not available, is the connection not encrypted at all?

How can I verify cryptographic status with a sender?

If you are within immediate distance of the chat partner:

If you are not near the chat partner, you can check the status manually in the “Encryption” dialog (user profile on Android/iOS or right-click a user’s chat-list item on desktop):

How can I check the encryption of messages?

Which standards are used for end-to-end-encryption?

What is the difference between verified groups and 1:1 chats with verified contacts?

Does Delta Chat support Perfect Forward Secrecy?

How does Delta Chat protect my Metadata?

Can I reuse my existing private key?

If you don’t have a key or don’t even know you would need one - don’t worry: Delta Chat generates one as needed, you don’t have to hit a button for it.

I can’t import my existing PGP key into Delta Chat.

With a very good chance, the problem is that your key is encrypted and/or uses a password. Such keys are not supported by Delta Chat. You may remove the passphrase encryption and the password and try the import again. If you want to keep your passphrase you’ll have to create an e-mail alias for use with Delta Chat such that Delta Chat’s key is tied to this e-mail alias.

Format wise, Delta Chat supports common OpenPGP private key formats, however, it is unlikely that we will support 100% of all private keys of any sources. This is also not the main focus of Delta Chat (in fact, the large majority of the Delta Chat users will not have any key before they start using Delta). However, we try to support private keys from other sources as good as possible.

Removing the password from the private key will be different, depending on the software you use to manage your PGP keys. With Enigmail, you can set your password to an empty value in the Key Management window. With GnuPG you can set it via the command line. For other programs, you can find a solution online.

Why don’t you use pEp (pretty easy privacy)?

Multi-client

Can I use Delta Chat on multiple devices at the same time?

If you want to use the same account on different devices, you should export a backup from the old device, and import it into the new device:

Are there any plans for introducing a Delta Chat Web Client?

Why can I choose not to watch the Inbox?

This is an experimental setting for some people who are experimenting with server-side rules. Not all providers support this, but with some you can move all mails with a “Chat-Version” header to the DeltaChat folder. Normally, this would be done by the Delta Chat app.

Watching the Inbox makes sense to turn off, if you have both:

In this case, Delta Chat doesn’t need to watch the Inbox.

What is the “Send Copy to Self” setting good for?

Sending a copy of your messages to yourself ensures that you receive your own messages on all devices. If you have multiple devices and don’t turn it on, you see only the messages from other people, and the messages you send from the current device.

The copy is sent to the Inbox, and then moved to the DeltaChat folder; it’s not put into the “Sent” folder. Delta Chat never uploads anything to the Sent folder because this would mean uploading a message twice (once through SMTP, and once through IMAP to Sent folder).

The default setting for copy-to-self is “no”.

Why can I choose to watch the “Sent” folder?

The only reason one wants to watch the Sent folder is if you are using another mail program (like Thunderbird) next to your Delta Chat app, and want your MUA to participate in chat conversations.

However, we recommend using the Delta Chat Desktop Client; you can download it on get.delta.chat. The option to watch the “Sent” folder might go away in the future. It was introduced at a time where there was no Delta Chat Desktop client available on all platforms.

Why can I choose not to watch the DeltaChat folder?

Some people use Delta Chat as a regular email client, and want to use the Inbox folder for their mail, instead of the DeltaChat folder. If you disable “Watch DeltaChat folder”, you should also disable “move chat messages to DeltaChat”. Otherwise, deleting messages or multi-device setups might not work properly.

Miscellaneous

Does Delta Chat work with my e-mail-provider?

If Delta Chat uses E-Mail, is it really an Instant Messenger?

Is Delta Chat compatible with Protonmail / Tutanota / Criptext?

I’m interested in the technical details. Can you tell me more?

How are Delta Chat developments funded?

First of all, Delta Chat does not receive any Venture Capital and is not indebted, and under no pressure to produce huge profits, or to sell users and their friends and family to advertisers (or worse).

Delta Chat developments have so far been funded from four major sources:

The monetary funding mentioned above was organized by merlinux GmbH in Freiburg (Germany), and then distributed to almost a dozen contributors.

Funding for 2020/2021 is yet to be determined. We are pursuing several opportunities with different organisations and partners. We also are considering to ask for donations. In fact, we experimentally started a little Delta Chat / Liberapay donation account but have not published this yet. There were also around 3-4K so far donated to Bjoern’s (the original author of Delta Chat) paypal and bitcoin donation channels.