# Pix-Art Messenger Pix-Art Messenger is a fork of the official [Conversations](https://github.com/siacs/Conversations) app with some modifications described under features. Pix-Art Messenger can be downloaded from github [releases](https://github.com/kriztan/Conversations/releases) ![screenshots](https://raw.githubusercontent.com/siacs/Conversations/master/screenshots.png) ## Design principles * Be as beautiful and easy to use as possible without sacrificing security or privacy * Rely on existing, well established protocols (XMPP) * Do not require a Google Account or specifically Google Cloud Messaging (GCM) * Require as few permissions as possible ## Features * End-to-end encryption with either [OTR](https://otr.cypherpunks.ca/) or [OpenPGP](http://www.openpgp.org/about_openpgp/) * Send and receive images as well as other kind of files * Share your location via an external [plug-in](https://play.google.com/store/apps/details?id=eu.siacs.conversations.sharelocation&referrer=utm_source%3Dgithub) * Indication when your contact has read your message * Intuitive UI that follows Android Design guidelines * Pictures / Avatars for your Contacts * Syncs with desktop client * Conferences (with support for bookmarks) * Address book integration * Multiple accounts / unified inbox * Very low impact on battery life our individual features: * accounts are hard linked to pix-art.de * increased avatar-sizes in account- and contact-details with prefering XMPP-avatars over addressbook avatars * in-app self updater with dayly check for updates * moved writing info from chatwindow into actionbar-subtitle * show lastseen info in actionbar-subtitle * display group chat members in actionbar-subtitle * images are transfered as JPEG * support more file-types for file-transfer (pdf, doc, docx, txt, m4a, m4b, mp3, mp2, wav, aac, aif, aiff, aifc, mid, midi, 3gpp, avi, mp4, mpeg, mpg, mpe, mov, 3gp, apk, vcf, ics, zip, rar) * show contacts name in locations shared in conferences ### XMPP Features Pix-Art Messenger works only with `pix-art.de`. However XMPP is an extensible protocol. These extensions are standardized as well in so called XEP's. Pix-Art Messenger supports a couple of these to make the overall user experience better. Our XMPP-Server is prosody and supports all of the listed XEP's: * [XEP-0065: SOCKS5 Bytestreams](http://xmpp.org/extensions/xep-0065.html) (or mod_proxy65). Will be used to transfer files if both parties are behind a firewall (NAT). * [XEP-0163: Personal Eventing Protocol](http://xmpp.org/extensions/xep-0163.html) for avatars * [XEP-0191: Blocking command](http://xmpp.org/extensions/xep-0191.html) lets you blacklist spammers or block contacts without removing them from your roster. * [XEP-0198: Stream Management](http://xmpp.org/extensions/xep-0198.html) allows XMPP to survive small network outages and changes of the underlying TCP connection. * [XEP-0280: Message Carbons](http://xmpp.org/extensions/xep-0280.html) which automatically syncs the messages you send to your desktop client and thus allows you to switch seamlessly from your mobile client to your desktop client and back within one conversation. * [XEP-0237: Roster Versioning](http://xmpp.org/extensions/xep-0237.html) mainly to save bandwidth on poor mobile connections * [XEP-0313: Message Archive Management](http://xmpp.org/extensions/xep-0313.html) synchronize message history with the server. Catch up with messages that were sent while Pix-Art Messenger was offline. * [XEP-0352: Client State Indication](http://xmpp.org/extensions/xep-0352.html) lets the server know whether or not Pix-Art Messenger is in the background. Allows the server to save bandwidth by withholding unimportant packages. * [XEP-0363: HTTP File Upload](http://xmpp.org/extensions/xep-0363.html) allows you to share files in conferences and with offline contacts. Requires an [additional component](https://github.com/siacs/HttpUploadComponent) on your server. ## Team #### Head of Development (original Conversations) * [Daniel Gultsch](https://github.com/inputmice) #### Head of Development (Pix-Art Messenger) * [Christian Schneppe](https://github.com/kriztan) #### Code Contributions (original Conversations) (In order of appearance) * [Rene Treffer](https://github.com/rtreffer) ([PRs](https://github.com/siacs/Conversations/pulls?utf8=%E2%9C%93&q=is%3Apr+author%3Artreffer+is%3Amerged)) * [Andreas Straub](https://github.com/strb) ([PRs](https://github.com/siacs/Conversations/pulls?utf8=%E2%9C%93&q=is%3Apr+author%3Astrb+is%3Amerged)) * [Alethea Butler](https://github.com/alethea) ([PRs](https://github.com/siacs/Conversations/pulls?utf8=%E2%9C%93&q=is%3Apr+author%3Aalethea+is%3Amerged)) * [M. Dietrich](https://github.com/emdete) ([PRs](https://github.com/siacs/Conversations/pulls?utf8=%E2%9C%93&q=is%3Apr+author%3Aemdete+is%3Amerged)) * [betheg](https://github.com/betheg) ([PRs](https://github.com/siacs/Conversations/pulls?utf8=%E2%9C%93&q=is%3Apr+author%3Abetheg+is%3Amerged)) * [Sam Whited](https://github.com/SamWhited) ([PRs](https://github.com/siacs/Conversations/pulls?utf8=%E2%9C%93&q=is%3Apr+author%3ASamWhited+is%3Amerged)) * [BrianBlade](https://github.com/BrianBlade) ([PRs](https://github.com/siacs/Conversations/pulls?utf8=%E2%9C%93&q=is%3Apr+author%3ABrianBlade+is%3Amerged)) #### Logo * [Ilia Rostovtsev](https://github.com/qooob) (Progress) * [Diego Turtulici](http://efesto.eigenlab.org/~diesys) (Original) * [fiaxh](https://github.com/fiaxh) (OMEMO) #### Translations Translations are managed on [Transifex](https://www.transifex.com/projects/p/conversations/) for original features Translations for our own features are managed on github. If you would like to help translation the app create a pull-request. ## FAQ ### General #### How do I install Pix-Art Messenger? Pix-Art Messenger is entirely open source and licensed under GPLv3. So if you are a software developer you can check out the sources from GitHub and use ant to build your apk file. Pix-Art Messenger can be downloaded from github [releases](https://github.com/kriztan/Conversations/releases) #### How do I create an account? With Pix-Art Messenger you can only create and use accounts on `pix-art.de`. You can create your own account for free. You only need a nickname and a password. You don't need to add `@pix-art.de` to your nickname. After creating your own `pix-art.de` account you'll find me in your contact list. If you have any questions about our app or our service feel free to ask me or join our support-conference `support@room.pix-art.de`. #### How does the address book integration work? The address book integration was designed to protect your privacy. Pix-Art Messenger neither uploads contacts from your address book to your server nor fills your address book with unnecessary contacts from your online roster. If you manually add a Jabber ID to your phones address book Pix-Art Messenger will use the name and the profile picture of this contact. To make the process of adding Jabber IDs to your address book easier you can click on the profile picture in the contact details within Pix-Art Messenger. This will start an "add to address book" intent with the JID as the payload. This doesn't require Pix-Art Messenger to have write permissions on your address book but also doesn't require you to copy/paste a JID from one app to another. #### I get 'delivery failed' on my messages If you get delivery failed on images it's probably because the recipient lost network connectivity during reception. In that case you can try it again at a later time. For text messages the answer to your question is a little bit more complex. When you see 'delivery failed' on text messages, it is always something that is being reported by the server. The most common reason for this is that the recipient failed to resume a connection. When a client loses connectivity for a short time the client usually has a five minute window to pick up that connection again. When the client fails to do so because the network connectivity is out for longer than that all messages sent to that client will be returned to the sender resulting in a delivery failed. Other less common reasons are that the message you sent didn't meet some criteria enforced by the server (too large, too many). Another reason could be that the recipient is offline and the server doesn't provide offline storage. Usually you are able to distinguish between these two groups in the fact that the first one happens always after some time and the second one happens almost instantly. #### Where can I see the status of my contacts? How can I set a status or priority? Statuses are a horrible metric. Setting them manually to a proper value rarely works because users are either lazy or just forget about them. Setting them automatically does not provide quality results either. Keyboard or mouse activity as indicator for example fails when the user is just looking at something (reading an article, watching a movie). Furthermore automatic setting of status always implies an impact on your privacy (are you sure you want everybody in your contact list to know that you have been using your computer at 4am‽). In the past status has been used to judge the likelihood of whether or not your messages are being read. This is no longer necessary. With Chat Markers (XEP-0333, supported by Pix-Art Messenger since 0.4) we have the ability to **know** whether or not your messages are being read. Similar things can be said for priorities. In the past priorities have been used (by servers, not by clients!) to route your messages to one specific client. With carbon messages (XEP-0280, supported by Pix-Art Messenger since 0.1) this is no longer necessary. Using priorities to route OTR messages isn't practical either because they are not changeable on the fly. Metrics like last active client (the client which sent the last message) are much better. Unfortunately these modern replacements for legacy XMPP features are not widely adopted. However Pix-Art Messenger should be an instant messenger for the future and instead of making Pix-Art Messenger compatible with the past we should work on implementing new, improved technologies and getting them into other XMPP clients as well. Making these status and priority optional isn't a solution either because Pix-Art Messenger is trying to get rid of old behaviours and set an example for other clients. ### Security #### Encryption methodes You can choose between different end-to-end encryption methodes, which are explained in the following lines. Our Server only accepts TLS encrypted connections to clients and only allows unencrypted connections to other server, if there is no way to encrypt the connections. If you are chatting with users to other servers, you should use an end-to-end encryption methode or ask me to look if the server-connections are encrypted or not. #### Why are there three end-to-end encryption methods and which one should I choose? In most cases OTR should be the encryption method of choice. It works out of the box with most contacts as long as they are online. However, openPGP can, in some cases, (message carbons to multiple clients) be more flexible. Unlike OTR, OMEMO works even when a contact is offline, and works with multiple devices. It also allows asynchronous file-transfer when the server has [HTTP File Upload](http://xmpp.org/extensions/xep-0363.html). However, OMEMO is not as widely supported as OTR and is currently implemented only by Pix-Art Messenger. OMEMO should be preffered over OTR for contacts who use Pix-Art Messenger. #### How do I use OpenPGP Before you continue reading you should note that the OpenPGP support in Pix-Art Messenger is experimental. This is not because it will make the app unstable but because the fundamental concepts of PGP aren't ready for widespread use. The way PGP works is that you trust Key IDs instead of JID's or email addresses. So in theory your contact list should consist of Public-Key-IDs instead of JID's. But of course no email or XMPP client out there implements these concepts. Plus PGP in the context of instant messaging has a couple of downsides: It is vulnerable to replay attacks, it is rather verbose, and decrypting and encrypting takes longer than OTR. It is however asynchronous and works well with message carbons. To use OpenPGP you have to install the open source app [OpenKeychain](http://www.openkeychain.org) and then long press on the account in manage accounts and choose renew PGP announcement from the contextual menu. #### How does the encryption for conferences work? For conferences the only supported encryption method is OpenPGP (OTR does not work with multiple participants). Every participant has to announce their OpenPGP key (see answer above). If you would like to send encrypted messages to a conference you have to make sure that you have every participant's public key in your OpenKeychain. Right now there is no check in Pix-Art Messenger to ensure that. You have to take care of that yourself. Go to the conference details and touch every key id (The hexadecimal number below a contact). This will send you to OpenKeychain which will assist you on adding the key. This works best in very small conferences with contacts you are already using OpenPGP with. This feature is regarded experimental. Pix-Art Messenger is the only client that uses XEP-0027 with conferences. (The XEP neither specifically allows nor disallows this.) #### I found a bug If you have troubles or problems please report them first into our support chat `support@room.pix-art.de`, so we can decide if it's an issue caused by our features or a global issue. Only global issues should be reported into the Conversations [issue tracker][issues]. If your app crashes please provide a stack trace. If you are experiencing misbehaviour please provide detailed steps to reproduce. Always mention whether you are running the latest Play Store version or the current HEAD. If you are having problems connecting to your XMPP server your file transfer doesn’t work as expected please always include a logcat debug output with your issue (see above). [issues]: https://github.com/siacs/Conversations/issues