Conversations/README.md

# Conversations

Conversations: the very last word in instant messaging

[![Google Play](http://developer.android.com/images/brand/en_generic_rgb_wo_60.png)](https://play.google.com/store/apps/details?id=eu.siacs.conversations&referrer=utm_source%3Dgithub) [![Amazon App Store](https://images-na.ssl-images-amazon.com/images/G/01/AmazonMobileApps/amazon-apps-store-us-black.png)](http://www.amazon.com/dp/B00WD35AAC/)

![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 [OMEMO](http://conversations.im/omemo/), [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


### XMPP Features

Conversations works with every XMPP server out there. However XMPP is an
extensible protocol. These extensions are standardized as well in so called
XEP's. Conversations supports a couple of these to make the overall user
experience better. There is a chance that your current XMPP server does not
support these extensions; therefore to get the most out of Conversations you
should consider either switching to an XMPP server that does or — even better —
run your own XMPP server for you and your friends. These XEP's are:

* [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 and OMEMO.
* [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 Conversations was
  offline.
* [XEP-0352: Client State Indication](http://xmpp.org/extensions/xep-0352.html) lets the server know whether or not
  Conversations 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. Alternatively, an [Ejabberd contrib-module](https://github.com/processone/ejabberd-contrib/tree/master/mod_http_upload) and a [Prosody module](http://modules.prosody.im/mod_http_upload.html) are available.

## Team

#### Head of Development

* [Daniel Gultsch](https://github.com/inputmice)

#### Code Contributions

(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/)

## FAQ

### General

#### How do I install Conversations?

Conversations 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 Gradle to
build your apk file.

The more convenient way — which not only gives you automatic updates but also
supports the further development of Conversations — is to buy the App in the
Google [Play Store](https://play.google.com/store/apps/details?id=eu.siacs.conversations&referrer=utm_source%3Dgithub).

Buying the App from the Play Store will also give you access to our [beta test](#beta).

#### I don't have a Google Account but I would still like to make a contribution

I accept donations over PayPal, Bitcoin and Flattr. For donations via PayPal you
can use the email address `donate@siacs.eu` or the button below.

[![Donate with PayPal](https://www.paypalobjects.com/en_US/i/btn/btn_donate_LG.gif)](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=CW3SYT3KG5PDL)

**Disclaimer:** I'm not a huge fan of PayPal and their business policies. For
larger contributions please get in touch with me beforehand and we can talk
about bank transfer (SEPA).

My Bitcoin Address is: `1NxSU1YxYzJVDpX1rcESAA3NJki7kRgeeu`


[![Flattr this!](http://api.flattr.com/button/flattr-badge-large.png)](https://flattr.com/submit/auto?user_id=inputmice&url=http%3A%2F%2Fconversations.siacs.eu&title=Conversations&tags=github&category=software)

#### How do I create an account?

XMPP, like email, is a federated protocol which means that there is not one
company you can create an 'official XMPP account' with. Instead there are
hundreds, or even thousands, of provider out there. To find one use a web search
engine of your choice. Or maybe your university has one. Or you can run your
own. Or ask a friend to run one. Once you've found one, you can use
Conversations to create an account. Just select 'register new account on server'
within the create account dialog.

#### Where can I set up a custom hostname / port
Conversations will automatically look up the SRV records for your domain name
which can point to any hostname port combination. If your server doesn’t provide
those please contact your admin and have them read
[this](http://prosody.im/doc/dns#srv_records)

#### I get 'Incompatible Server'

As regular user you should be picking a different server. The server you selected
is probably insecure and/or very old.

If you are a server administrator you should make sure that your server provides
STARTTLS. XMPP over TLS (on a different port) is not sufficient.

On rare occasions this error message might also be caused by a server not providing
a login (SASL) mechanism that Conversations is able to handle. Conversations supports
SCRAM-SHA1, PLAIN, EXTERNAL (client certs) and DIGEST-MD5.

#### Conversations doesn't work for me. Where can I get help?

You can join our conference room on `conversations@conference.siacs.eu`.
A lot of people in there are able to answer basic questions about the usage of
Conversations or can provide you with tips on running your own XMPP server. If
you found a bug or your app crashes please read the Developer / Report Bugs
section of this document.

#### I need professional support with Conversations or setting up my server

I'm available for hire. Contact me at `inputmice@siacs.eu`.

#### How does the address book integration work?

The address book integration was designed to protect your privacy. Conversations
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 Conversations 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 Conversations. This will start an "add to address book" intent
with the JID as the payload. This doesn't require Conversations 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 Conversations 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 Conversations 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 Conversations should be an instant messenger for the future and
instead of making Conversations 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
Conversations is trying to get rid of old behaviours and set an example for
other clients.

#### Conversations is missing a certain feature

I'm open for new feature suggestions. You can use the [issue tracker][issues] on
GitHub.  Please take some time to browse through the issues to see if someone
else already suggested it. Be assured that I read each and every ticket. If I
like it I will leave it open until it's implemented. If I don't like it I will
close it (usually with a short comment). If I don't comment on an feature
request that's probably a good sign because this means I agree with you.
Commenting with +1 on either open or closed issues won't change my mind, nor
will it accelerate the development.

#### You closed my feature request but I want it really really badly

Just write it yourself and send me a pull request. If I like it I will happily
merge it if I don't at least you and like minded people get to enjoy it.

#### I need a feature and I need it now!

I am available for hire. Contact me via XMPP: `inputmice@siacs.eu`

### Security

#### 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 Conversations. OMEMO should be preffered over OTR for contacts who use Conversations.

#### How do I use OpenPGP

Before you continue reading you should note that the OpenPGP support in
Conversations 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 Conversations 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. Conversations is the only client that uses
XEP-0027 with conferences. (The XEP neither specifically allows nor disallows
this.)

### Development

<a name="beta"></a>
#### Beta testing
If you bought the App on [Google Play](https://play.google.com/store/apps/details?id=eu.siacs.conversations)
you can get access to the latest beta version by joining the
[Conversations Beta Testers](https://plus.google.com/communities/107649347599361240873)
community on Google+ and then using [this link](https://play.google.com/apps/testing/eu.siacs.conversations)
to sign up for the beta test.

#### How do I build Conversations

Make sure to have ANDROID_HOME point to your Android SDK

    git clone https://github.com/siacs/Conversations.git
    cd Conversations
    ./gradlew build


[![Build Status](https://travis-ci.org/siacs/Conversations.svg?branch=development)](https://travis-ci.org/siacs/Conversations)

### How do I update/add external libraries?

If the library you want to update is in Maven Central or JCenter (or has its own
Maven repo), add it or update its version in `build.gradle`. If the library is
in the `libs/` directory, you can update it using a subtree merge by doing the
following (using `minidns` as an example):

    git remote add minidns https://github.com/rtreffer/minidns.git
    git fetch minidns
    git merge -s subtree minidns master

To add a new dependency to the `libs/` directory (replacing "name", "branch" and
"url" as necessary):

    git remote add name url
    git merge -s ours --no-commit name/branch
    git read-tree --prefix=libs/name -u name/branch
    git commit -m "Subtree merged in name"

#### How do I debug Conversations

If something goes wrong Conversations usually exposes very little information in
the UI (other than the fact that something didn't work). However with adb
(android debug bridge) you squeeze some more information out of Conversations.
These information are especially useful if you are experiencing trouble with
your connection or with file transfer.

    adb -d logcat -v time -s conversations

#### I found a bug

Please report it to our [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