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B. Petersen
699 lines
28 KiB
HTML
699 lines
28 KiB
HTML
<!DOCTYPE html>
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<html><head><meta charset="UTF-8" /><link rel="stylesheet" href="../help.css" /></head><body><ul id="top">
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<li><a href="#what-is-delta-chat">What is Delta Chat?</a>
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<ul>
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<li><a href="#how-can-i-find-people-to-chat-with">How can I find people to chat with?</a></li>
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<li><a href="#what-are-the-advantages-of-delta-chat-compared-to-other-messengers">What are the advantages of Delta Chat compared to other messengers?</a></li>
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<li><a href="#which-messages-do-appear-in-delta-chat">Which messages do appear in Delta Chat?</a></li>
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<li><a href="#what-about-spam">What about spam?</a></li>
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<li><a href="#does-delta-chat-support-images-videos-and-other-attachments">Does Delta Chat support images, videos and other attachments?</a></li>
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<li><a href="#who-sees-my-profile-picture">Who sees my profile picture?</a></li>
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<li><a href="#does-delta-chat-support-html-e-mails">Does Delta Chat support HTML e-mails?</a></li>
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<li><a href="#why-do-i-have-to-enter-my-e-mail-password-into-delta-chat-is-this-secure">Why do I have to enter my E-Mail password into Delta Chat? Is this secure?</a></li>
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<li><a href="#which-android-permissions-does-delta-chat-need">Which Android permissions does Delta Chat need?</a></li>
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</ul>
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</li>
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<li><a href="#groups">Groups</a>
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<ul>
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<li><a href="#creation-of-a-group">Creation of a group</a></li>
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<li><a href="#add-members-to-a-group">Add members to a group</a></li>
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<li><a href="#what-is-a-verified-group-why-is-it-experimental">What is a verified group? Why is it experimental?</a></li>
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<li><a href="#i-have-deleted-myself-by-accident">I have deleted myself by accident.</a></li>
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<li><a href="#i-do-not-want-to-receive-the-messages-of-a-group-any-longer">I do not want to receive the messages of a group any longer.</a></li>
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</ul>
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</li>
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<li><a href="#encryption">Encryption</a>
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<ul>
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<li><a href="#does-delta-chat-support-end-to-end-encryption">Does Delta Chat support end-to-end-encryption?</a></li>
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<li><a href="#what-do-i-have-to-do-to-activate-the-end-to-end-encryption">What do I have to do to activate the end-to-end-encryption?</a></li>
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<li><a href="#if-end-to-end-encryption-is-not-available-is-the-connection-not-encrypted-at-all">If end-to-end-encryption is not available, is the connection not encrypted at all?</a></li>
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<li><a href="#how-can-i-verify-cryptographic-status-with-a-sender">How can I verify cryptographic status with a sender?</a></li>
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<li><a href="#how-can-i-check-the-encryption-of-messages">How can I check the encryption of messages?</a></li>
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<li><a href="#which-standards-are-used-for-end-to-end-encryption">Which standards are used for end-to-end-encryption?</a></li>
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<li><a href="#what-is-the-difference-between-verified-groups-and-11-chats-with-verified-contacts">What is the difference between verified groups and 1:1 chats with verified contacts?</a></li>
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<li><a href="#does-delta-chat-support-perfect-forward-secrecy">Does Delta Chat support Perfect Forward Secrecy?</a></li>
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<li><a href="#how-does-delta-chat-protect-my-metadata">How does Delta Chat protect my Metadata?</a></li>
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<li><a href="#can-i-re-use-my-existing-private-key">Can I re-use my existing private key?</a></li>
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<li><a href="#i-cant-import-my-existing-pgp-key-into-delta-chat">I can’t import my existing PGP key into Delta Chat.</a></li>
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<li><a href="#why-dont-you-use-pep-pretty-easy-privacy">Why don’t you use pEp (pretty easy privacy)?</a></li>
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</ul>
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</li>
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<li><a href="#multiclient">Multi-client</a>
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<ul>
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<li><a href="#can-i-use-delta-chat-on-multiple-devices-at-the-same-time">Can I use Delta Chat on multiple devices at the same time?</a></li>
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</ul>
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</li>
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<li><a href="#miscellaneous">Miscellaneous</a>
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<ul>
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<li><a href="#does-delta-chat-work-with-my-e-mail-provider">Does Delta Chat work with <em>my</em> e-mail-provider?</a></li>
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<li><a href="#im-interested-in-the-technical-details-can-you-tell-me-more">I’m interested in the technical details. Can you tell me more?</a></li>
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</ul>
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</li>
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</ul>
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<h2 id="what-is-delta-chat">
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What is Delta Chat? <a href="#what-is-delta-chat" class="anchor"></a>
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</h2>
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<p>Delta Chat is a new chat app that sends messages via e-mails, encrypted if possible, with Autocrypt.
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<strong>You do not have to sign up anywhere, just use your existing e-mail account with Delta Chat.</strong></p>
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<h3 id="how-can-i-find-people-to-chat-with">
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How can I find people to chat with? <a href="#how-can-i-find-people-to-chat-with" class="anchor"></a>
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</h3>
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<p>With Delta Chat, you can write to every existing e-mail address - even
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if the recipient is not using the Delta Chat app. No need for the
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recipient to install the same app as yours, as with other messengers.</p>
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<h3 id="what-are-the-advantages-of-delta-chat-compared-to-other-messengers">
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What are the advantages of Delta Chat compared to other messengers? <a href="#what-are-the-advantages-of-delta-chat-compared-to-other-messengers" class="anchor"></a>
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</h3>
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<ul>
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<li><em>Independent</em> of any company or services. <em>You</em> own your data.</li>
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<li>Your data is not saved on a central server unless all users are using
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the same e-mail servers</li>
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<li>You do not distribute your address book to anyone.</li>
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<li><em>Fast</em> by the use of Push-IMAP.</li>
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<li><em>Largest userbase</em> - recipients <em>not</em> using Delta Chat can be reached as well.</li>
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<li><em>Compatible</em> - not only to itself.</li>
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<li><em>Elegant</em> and <em>simple</em> user interface.</li>
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<li><em>Distributed</em> system.</li>
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<li><em>No Spam</em> - only messages of known users are shown by default.</li>
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<li><em>Reliable</em> - safe for professional use.</li>
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<li><em>Trustworthy</em> - can even be used for business messages.</li>
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<li><em>Copyleft</em> and <em>Standards</em> based libre software.</li>
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</ul>
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<h3 id="which-messages-do-appear-in-delta-chat">
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Which messages do appear in Delta Chat? <a href="#which-messages-do-appear-in-delta-chat" class="anchor"></a>
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</h3>
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<p>Delta Chat automatically shows:</p>
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<ul>
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<li>Messages from contacts in your <strong>address book</strong></li>
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<li>Messages from contacts <strong>contacted by you</strong></li>
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<li><strong>Replies</strong> to messages sent by you</li>
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</ul>
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<p>Other messages do not appear automatically, and are to be found in the main menu at <strong>Contact requests</strong>. If desired a chat can be started from there.</p>
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<h3 id="what-about-spam">
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What about spam? <a href="#what-about-spam" class="anchor"></a>
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</h3>
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<ul>
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<li>Messages in common spam folders are ignored and contained addresses are not considered as known contacts.</li>
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<li>As messages from unknown contacts do not pop up automatically, normally, there is <strong>no spam</strong>.</li>
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<li>However, if needed, you can <strong>block</strong> any contact.</li>
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</ul>
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<h3 id="does-delta-chat-support-images-videos-and-other-attachments">
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Does Delta Chat support images, videos and other attachments? <a href="#does-delta-chat-support-images-videos-and-other-attachments" class="anchor"></a>
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</h3>
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<ul>
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<li>Yes. Beside the plain text, all e-mail attachments are displayed as separate messages. Outgoing messages get attachments as needed automatically.</li>
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</ul>
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<h3 id="who-sees-my-profile-picture">
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Who sees my profile picture? <a href="#who-sees-my-profile-picture" class="anchor"></a>
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</h3>
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<ul>
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<li>
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<p>You can add a profile picture in your settings. If you write to your contacts
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or add them via QR code, they automatically see it as your profile picture.</p>
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</li>
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<li>
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<p>Contacts who don’t use Delta Chat see it as an E-Mail attachment.</p>
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</li>
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<li>
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<p>For privacy reasons, no one sees your profile picture until you write a
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message to them.</p>
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</li>
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<li>
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<p>Your profile picture isn’t sent with every message, but regularly enough that
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your contacts will re-receive your profile picture, even if they add a new
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device.</p>
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</li>
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</ul>
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<h3 id="does-delta-chat-support-html-e-mails">
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Does Delta Chat support HTML e-mails? <a href="#does-delta-chat-support-html-e-mails" class="anchor"></a>
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</h3>
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<ul>
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<li>Yes. If incoming e-mail lacks a plain text part, HTML-emails is converted to plain text in the app. Outgoing e-mails always use plain text.</li>
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</ul>
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<h3 id="why-do-i-have-to-enter-my-e-mail-password-into-delta-chat-is-this-secure">
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Why do I have to enter my E-Mail password into Delta Chat? Is this secure? <a href="#why-do-i-have-to-enter-my-e-mail-password-into-delta-chat-is-this-secure" class="anchor"></a>
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</h3>
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<p>As with other E-Mail programs like Thunderbird, K9-Mail, or Outlook, the
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program needs the password so you can use it to send mails. Of course, the
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password is stored only on your device. The password is only transmitted to
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your E-Mail provider (when you login), which has access to your mails anyway.</p>
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<p>If you use an E-Mail provider with OAuth2 support like gmail.com or yandex.ru,
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there is no need to store your password on the device. In this case, only an
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access token is used.</p>
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<p>As Delta Chat is Open Source, you can check the <a href="https://github.com/deltachat/deltachat-core-rust/blob/master/src/login_param.rs">Source
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Code</a>
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if you want to verify that your credentials are handled securely. We are happy
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about feedback which makes the app more secure for all of our users.</p>
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<h3 id="which-android-permissions-does-delta-chat-need">
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Which Android permissions does Delta Chat need? <a href="#which-android-permissions-does-delta-chat-need" class="anchor"></a>
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</h3>
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<ul>
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<li>Camera <em>(can be disallowed)</em>
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<ul>
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<li>take pictures and videos: for sending Photos</li>
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</ul>
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</li>
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<li>Contacts <em>(can be disallowed)</em>
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<ul>
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<li>read your contacts: to discover contacts to chat with</li>
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</ul>
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</li>
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<li>Location <em>(can be disallowed)</em>
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<ul>
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<li>access approximate location (network location sources): for the location streaming feature</li>
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<li>access precise location (GPS and network location sources): for the location streaming feature</li>
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</ul>
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</li>
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<li>Microphone <em>(can be disallowed)</em>
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<ul>
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<li>record audio: for audio messages</li>
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</ul>
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</li>
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<li>Storage <em>(can be disallowed)</em>
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<ul>
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<li>modify or delete the contents of your SD card: to download message attachments</li>
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<li>read the contents of your SD card: to share files with your contacts</li>
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</ul>
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</li>
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<li>Other app capabilities
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<ul>
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<li>change your audio settings: so you can choose ring tones and volume for notifications and audio messages</li>
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<li>run at startup: so you don’t have to start Delta Chat manually</li>
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<li>control vibration: for notifications</li>
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<li>view network connections: to connect to your E-Mail provider</li>
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<li>prevent phone from sleeping: so you can easier copy the security code during the Autocrypt Setup Message</li>
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<li>have full network access: to connect to your E-Mail provider</li>
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<li>view Wi-Fi connections: to connect to your E-Mail provider</li>
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<li>ask to ignore battery optimisations: for users who want to receive messages all the time</li>
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</ul>
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</li>
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</ul>
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<h2 id="groups">
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Groups <a href="#groups" class="anchor"></a>
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</h2>
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<h3 id="creation-of-a-group">
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Creation of a group <a href="#creation-of-a-group" class="anchor"></a>
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</h3>
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<ul>
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<li>Select <strong>Add group</strong> from the “Sandwich menu” in the upper right corner of the chat overview.</li>
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<li>On the following screen, select the <strong>group members</strong> and hit the check mark in the upper right corner. After that, you can define a <strong>group name</strong>.</li>
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<li>As soon as you write the <strong>first message</strong> in the group, all members are informed about the new group and can answer in the group (as long as you do not write a message in the group the group is invisible to the members).</li>
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</ul>
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<h3 id="add-members-to-a-group">
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Add members to a group <a href="#add-members-to-a-group" class="anchor"></a>
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</h3>
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<ul>
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<li>Every group member has the <strong>same rights</strong> as any other. For this reason every one can delete every member or add new ones.</li>
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<li>To add or delete members, click on the group name in the chat.</li>
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</ul>
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<h3 id="what-is-a-verified-group-why-is-it-experimental">
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What is a verified group? Why is it experimental? <a href="#what-is-a-verified-group-why-is-it-experimental" class="anchor"></a>
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</h3>
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<ul>
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<li>
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<p>A verified group is a chat that gurantees safety against an active
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attacker. All Messages in a verified chat view are e2e-encrypted, and
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members can join by scanning a “QR invite code”. All members are thus
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connected with each other through a chain of invites, which guarantee
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cryptographic consistency against active network or provider attacks.
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See <a href="https://countermitm.readthedocs.io/en/latest/new.html">countermitm.readthedocs.io</a>
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for the R&D behind this feature.</p>
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</li>
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<li>
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<p>As of Dec 2019, a “verified group” remains an experimental feature.
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It is continously improved and many bugs have been fixed since the
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original introduction in 2018. However, there remain cases, especially
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with large groups where inconsistencies can occure, or messages become
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unreadable. Early 2020 a security review is upcoming, and several new
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developments around qr-join protocols are taking place so chances
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are we remove the “experimental” label not too far in the future.</p>
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</li>
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</ul>
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<h3 id="i-have-deleted-myself-by-accident">
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I have deleted myself by accident. <a href="#i-have-deleted-myself-by-accident" class="anchor"></a>
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</h3>
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<ul>
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<li>As you’re no longer a group member, you cannot add yourself again.
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However, no problem, just ask any other group member in a normal chat to re-add you.</li>
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</ul>
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<h3 id="i-do-not-want-to-receive-the-messages-of-a-group-any-longer">
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I do not want to receive the messages of a group any longer. <a href="#i-do-not-want-to-receive-the-messages-of-a-group-any-longer" class="anchor"></a>
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</h3>
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<ul>
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<li>
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<p>Either delete yourself from the member list or delete the whole chat.
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If you want to join the group again later on, ask another group member to add you again.</p>
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</li>
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<li>
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<p>As an alternative, you can also “Mute” a group - doing so means you get all messages and
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can still write, but are no longer notified of any new messages.</p>
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</li>
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</ul>
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<h2 id="encryption">
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Encryption <a href="#encryption" class="anchor"></a>
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</h2>
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<h3 id="does-delta-chat-support-end-to-end-encryption">
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Does Delta Chat support end-to-end-encryption? <a href="#does-delta-chat-support-end-to-end-encryption" class="anchor"></a>
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</h3>
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<ul>
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<li>Yes. Delta Chat implements the Autocrypt Level 1 standard and can
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thus E2E-encrypt messages with other Autocrypt-capable apps.</li>
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</ul>
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<h3 id="what-do-i-have-to-do-to-activate-the-end-to-end-encryption">
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What do I have to do to activate the end-to-end-encryption? <a href="#what-do-i-have-to-do-to-activate-the-end-to-end-encryption" class="anchor"></a>
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</h3>
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<ul>
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<li>
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<p>Nothing.</p>
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</li>
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<li>
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<p>Delta Chat apps (and other <a href="https://autocrypt.org">Autocrypt</a>-compatible
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e-mail apps) share the keys required for end-to-end-encryption automatically
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as the first messages are sent.
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After this, all subsequent messages are encrypted end-to-end automatically.
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If one of the chat partners uses a non-Autocrypt e-mail app, subsequent
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messages are not encrypted until an Autocrypt-compliant app is available again.</p>
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</li>
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<li>
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<p>If you want to <em>turn off</em> the end-to-end-encryption,
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use the corresponding setting in “Settings / Advanced settings”.</p>
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</li>
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</ul>
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<h3 id="if-end-to-end-encryption-is-not-available-is-the-connection-not-encrypted-at-all">
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If end-to-end-encryption is not available, is the connection not encrypted at all? <a href="#if-end-to-end-encryption-is-not-available-is-the-connection-not-encrypted-at-all" class="anchor"></a>
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</h3>
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<ul>
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<li>With most mail servers, Delta Chat establishes <em>transport encryption</em>
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(<a href="https://en.wikipedia.org/wiki/Transport_Layer_Security">TLS</a>).
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This only secures the connection between your device and your e-mail
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server. Whereas e2e-encryption provides safety between
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your device and a friend’s device.</li>
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</ul>
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<h3 id="how-can-i-verify-cryptographic-status-with-a-sender">
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How can I verify cryptographic status with a sender? <a href="#how-can-i-verify-cryptographic-status-with-a-sender" class="anchor"></a>
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</h3>
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|
||
<p>The user’s profile shows some additional info:</p>
|
||
|
||
<ul>
|
||
<li>
|
||
<p>Tap “QR Invite code” on Android and then use the “Scan QR code”
|
||
button on another device to scan this code. If both devices are online,
|
||
they will introduce a chat channel with each-other (if it doesn’t exist already)
|
||
and the encryption keys will also be verified. Both will see a
|
||
“sender verified” system message in their 1:1 chat.</p>
|
||
</li>
|
||
<li>
|
||
<p>For end-to-end-encryption, Delta Chat shows two fingerprints there.
|
||
If the same fingerprints appears on your chat partner’s device,
|
||
the connection is safe.</p>
|
||
</li>
|
||
<li>
|
||
<p>For transport encryption, this state is just shown there</p>
|
||
</li>
|
||
</ul>
|
||
|
||
<h3 id="how-can-i-check-the-encryption-of-messages">
|
||
|
||
|
||
How can I check the encryption of messages? <a href="#how-can-i-check-the-encryption-of-messages" class="anchor"></a>
|
||
|
||
|
||
</h3>
|
||
|
||
<ul>
|
||
<li>
|
||
<p>If a little <strong>padlock</strong> is shown beside a message, this denotes the message is end-to-end-encrypted <em>and</em> is sent from the given sender <em>and</em> that your answer will be end-to-end-encrypted as well.</p>
|
||
</li>
|
||
<li>
|
||
<p>If there is <strong>no padlock</strong>, the message is usually transported unencrypted e.g. because you or the sender have turned off end-to-end-encryption, or the sender uses an app without support for end-to-end-encryption.</p>
|
||
</li>
|
||
</ul>
|
||
|
||
<h3 id="which-standards-are-used-for-end-to-end-encryption">
|
||
|
||
|
||
Which standards are used for end-to-end-encryption? <a href="#which-standards-are-used-for-end-to-end-encryption" class="anchor"></a>
|
||
|
||
|
||
</h3>
|
||
|
||
<ul>
|
||
<li><a href="https://autocrypt.org">Autocrypt</a> is used for establishing
|
||
e2e-encryption with other Delta Chat and other Autocrypt-capable mail apps.
|
||
Autocrypt uses a limited subset of OpenPGP functionality. Moreover,
|
||
Delta Chat implements the “countermitm” protocols to achieve
|
||
protection against active network attacks, going beyond the opportunistic
|
||
base protection of Autocrypt, see questions about “Verified Groups”.</li>
|
||
</ul>
|
||
|
||
<h3 id="what-is-the-difference-between-verified-groups-and-11-chats-with-verified-contacts">
|
||
|
||
|
||
What is the difference between verified groups and 1:1 chats with verified contacts? <a href="#what-is-the-difference-between-verified-groups-and-11-chats-with-verified-contacts" class="anchor"></a>
|
||
|
||
|
||
</h3>
|
||
|
||
<ul>
|
||
<li>
|
||
<p>1:1 chats with a verified contact and verified groups are not the same, even
|
||
if there are only 2 people in the verified group. One difference is that you
|
||
could easily add more people to the group, but there are other implications as
|
||
well.</p>
|
||
</li>
|
||
<li>
|
||
<p>Verified groups are invariably secured. Any breakage (cleartext or wrongly
|
||
signed messages etc.) will be flagged and such messages will not be shown in
|
||
this chat. You can trust all messages in this verified-checkmark chat to have
|
||
not been read/altered by middle parties.</p>
|
||
</li>
|
||
<li>
|
||
<p>1:1 chats are opportunistic, it is meant to allow people to communicate no
|
||
matter if they change e-mail clients, devices, setups etc. That’s why there
|
||
is no verification checkmark, even if you have verified the contact.</p>
|
||
</li>
|
||
</ul>
|
||
|
||
<h3 id="does-delta-chat-support-perfect-forward-secrecy">
|
||
|
||
|
||
Does Delta Chat support Perfect Forward Secrecy? <a href="#does-delta-chat-support-perfect-forward-secrecy" class="anchor"></a>
|
||
|
||
|
||
</h3>
|
||
|
||
<ul>
|
||
<li>
|
||
<p>No, OpenPGP doesn’t support Perfect Forward Secrecy. Perfect Forward Secrecy
|
||
works session-oriented, but E-Mail is asynchronous by nature
|
||
and often used from multiple devices independently. This means that if your
|
||
Delta Chat private key is leaked, and someone has a record
|
||
of all your in-transit messages, they will be able to read them.</p>
|
||
</li>
|
||
<li>
|
||
<p>Note that if anyone has seized or hacked your running phone, they will
|
||
typically be able to read all messages, no matter if Perfect Forward Secrecy
|
||
is in place or not. Having access to a single device from a member of a group,
|
||
will typically expose a lot of the social graph. Using e-mail addresses that
|
||
are not easily tracked back to persons helps group members to stay safer from
|
||
the effects of device seizure.</p>
|
||
</li>
|
||
<li>
|
||
<p>We are sketching ways to protect communications better against the event
|
||
of device seizure.</p>
|
||
</li>
|
||
</ul>
|
||
|
||
<h3 id="how-does-delta-chat-protect-my-metadata">
|
||
|
||
|
||
How does Delta Chat protect my Metadata? <a href="#how-does-delta-chat-protect-my-metadata" class="anchor"></a>
|
||
|
||
|
||
</h3>
|
||
|
||
<ul>
|
||
<li>
|
||
<p>As Delta Chat is a decentralized messenger, the metadata of Delta Chat users
|
||
are not stored on a single central server. However, they are stored on the mail
|
||
servers of the sender and the recipient of a message.</p>
|
||
</li>
|
||
<li>
|
||
<p>Each mail server currently know about who sent and who received a message by
|
||
inspecting the unencrypted To/Cc headers and thus determine which e-mail addresses
|
||
are part of a group. Delta Chat itself could avoid unencrypted To/Cc headers quite
|
||
and always put them only into the encrypted section. See
|
||
<a href="https://github.com/deltachat/deltachat-core-rust/issues/1032">Avoid sending To/CC headers for verified groups</a>.
|
||
For opportunistic chats the main concern is how it affects other mail apps who
|
||
might participate in chats.</p>
|
||
</li>
|
||
<li>
|
||
<p>Many other e-mail headers, in particular the “Subject” header, are
|
||
end-to-end-encryption protected, see also this upcoming <a href="https://datatracker.ietf.org/doc/draft-autocrypt-lamps-protected-headers/">IETF
|
||
RFC</a>.</p>
|
||
</li>
|
||
</ul>
|
||
|
||
<h3 id="can-i-re-use-my-existing-private-key">
|
||
|
||
|
||
Can I re-use my existing private key? <a href="#can-i-re-use-my-existing-private-key" class="anchor"></a>
|
||
|
||
|
||
</h3>
|
||
|
||
<ul>
|
||
<li>
|
||
<p>Yes. The best way is to send an Autocrypt Setup Message from the other e-mail client. Look for something like <strong>Start Autocrypt Setup Transfer</strong> in the settings of the other client and follow the instructions shown there.</p>
|
||
</li>
|
||
<li>
|
||
<p>Alternatively, you can import the key manually in “Advanced settings / Manage private keys”. Caution: Make sure the key is not protected by a password, or remove the password beforehand.</p>
|
||
</li>
|
||
</ul>
|
||
|
||
<p>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.</p>
|
||
|
||
<h3 id="i-cant-import-my-existing-pgp-key-into-delta-chat">
|
||
|
||
|
||
I can’t import my existing PGP key into Delta Chat. <a href="#i-cant-import-my-existing-pgp-key-into-delta-chat" class="anchor"></a>
|
||
|
||
|
||
</h3>
|
||
|
||
<p>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.</p>
|
||
|
||
<p>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.</p>
|
||
|
||
<p>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 <a href="https://github.com/deltachat/deltachat-android/issues/98#issuecomment-378383429">via the command
|
||
line</a>.
|
||
For other programs, you can find a solution online.</p>
|
||
|
||
<h3 id="why-dont-you-use-pep-pretty-easy-privacy">
|
||
|
||
|
||
Why don’t you use pEp (pretty easy privacy)? <a href="#why-dont-you-use-pep-pretty-easy-privacy" class="anchor"></a>
|
||
|
||
|
||
</h3>
|
||
|
||
<ul>
|
||
<li>Delta Chat uses the Autocrypt e2e-encryption standard. For
|
||
a discussion of Autocrypt and pEp, see the <a href="https://autocrypt.org/faq.html#how-does-autocrypt-differ-from-pep">Autocrypt
|
||
FAQ</a>.</li>
|
||
</ul>
|
||
|
||
<h2 id="multiclient">
|
||
|
||
|
||
Multi-client <a href="#multiclient" class="anchor"></a>
|
||
|
||
|
||
</h2>
|
||
|
||
<h3 id="can-i-use-delta-chat-on-multiple-devices-at-the-same-time">
|
||
|
||
|
||
Can I use Delta Chat on multiple devices at the same time? <a href="#can-i-use-delta-chat-on-multiple-devices-at-the-same-time" class="anchor"></a>
|
||
|
||
|
||
</h3>
|
||
|
||
<p>If you want to use the <strong>same account</strong> on different (Autocrypt
|
||
capable) devices, you have to sync their encryption capabilities:</p>
|
||
|
||
<ul>
|
||
<li>
|
||
<p>On the first device, choose “Advanced settings / Send Autocrypt Setup message”
|
||
and click until a “security number” is shown.</p>
|
||
</li>
|
||
<li>
|
||
<p>On the other device, wait for the “Autocrypt Setup Message” to
|
||
arrive and click on it, which should prompt you for the security number.</p>
|
||
</li>
|
||
<li>
|
||
<p>You are now synchronized, and can use both devices for
|
||
sending and receiving E2E-encrypted messages with your communication partners.</p>
|
||
</li>
|
||
</ul>
|
||
|
||
<h2 id="miscellaneous">
|
||
|
||
|
||
Miscellaneous <a href="#miscellaneous" class="anchor"></a>
|
||
|
||
|
||
</h2>
|
||
|
||
<h3 id="does-delta-chat-work-with-my-e-mail-provider">
|
||
|
||
|
||
Does Delta Chat work with <em>my</em> e-mail-provider? <a href="#does-delta-chat-work-with-my-e-mail-provider" class="anchor"></a>
|
||
|
||
|
||
</h3>
|
||
|
||
<ul>
|
||
<li>With a rather good chance: Yes :)<br />
|
||
However, some providers need special options to work properly,
|
||
see <a href="https://providers.delta.chat">Provider Overview</a></li>
|
||
</ul>
|
||
|
||
<h3 id="im-interested-in-the-technical-details-can-you-tell-me-more">
|
||
|
||
|
||
I’m interested in the technical details. Can you tell me more? <a href="#im-interested-in-the-technical-details-can-you-tell-me-more" class="anchor"></a>
|
||
|
||
|
||
</h3>
|
||
|
||
<ul>
|
||
<li>See <a href="https://github.com/deltachat/deltachat-android/blob/master/standards.md#standards-used-in-delta-chat">Standards used in Delta Chat</a>.</li>
|
||
</ul>
|
||
|
||
|
||
|
||
|
||
|
||
</body></html> |