README.md

  1<h1 align="center">Conversations</h1>
  2
  3<p align="center">Conversations: the very last word in instant messaging</p>
  4
  5<p align="center">
  6    <a href="https://conversations.im/j/conversations@conference.siacs.eu">
  7        <img src="https://inverse.chat/badge.svg?room=conversations@conference.siacs.eu"
  8             alt="chat on our conference room">
  9    </a>
 10    <a href="https://travis-ci.org/siacs/Conversations">
 11        <img src="https://travis-ci.org/siacs/Conversations.svg?branch=master"
 12             alt="build status">
 13    </a>
 14    <a href="https://bountysource.com/teams/siacs">
 15        <img src="https://api.bountysource.com/badge/tracker?tracker_id=519483" alt="Bountysource">
 16    </a>
 17</p>
 18
 19<p align="center">
 20    <a href="https://play.google.com/store/apps/details?id=eu.siacs.conversations&amp;referrer=utm_source%3Dgithub">
 21       <img src="https://conversations.im/images/en-play-badge.png"
 22            alt="Google Play">
 23            </a>
 24    <a href="http://www.amazon.com/dp/B00WD35AAC/">
 25        <img src="https://images-na.ssl-images-amazon.com/images/G/01/AmazonMobileApps/amazon-apps-store-us-black.png"
 26             alt="Amazon App Store">
 27    </a>
 28</p>
 29
 30![screenshots](https://raw.githubusercontent.com/siacs/Conversations/master/screenshots.png)
 31
 32## Design principles
 33
 34* Be as beautiful and easy to use as possible without sacrificing security or
 35  privacy
 36* Rely on existing, well established protocols (XMPP)
 37* Do not require a Google Account or specifically Google Cloud Messaging (GCM)
 38
 39## Features
 40
 41* End-to-end encryption with [OMEMO](http://conversations.im/omemo/) or [OpenPGP](http://openpgp.org/about/)
 42* Send and receive images as well as other kind of files
 43* Share your location
 44* Send voice messages
 45* Indication when your contact has read your message
 46* Intuitive UI that follows Android Design guidelines
 47* Pictures / Avatars for your Contacts
 48* Synchronizes with desktop client
 49* Conferences (with support for bookmarks)
 50* Address book integration
 51* Multiple accounts / unified inbox
 52* Very low impact on battery life
 53
 54
 55### XMPP Features
 56
 57Conversations works with every XMPP server out there. However XMPP is an
 58extensible protocol. These extensions are standardized as well in so called
 59XEP's. Conversations supports a couple of these to make the overall user
 60experience better. There is a chance that your current XMPP server does not
 61support these extensions; therefore to get the most out of Conversations you
 62should consider either switching to an XMPP server that does or — even better —
 63run your own XMPP server for you and your friends. These XEP's are:
 64
 65* [XEP-0065: SOCKS5 Bytestreams](http://xmpp.org/extensions/xep-0065.html) (or mod_proxy65). Will be used to transfer
 66  files if both parties are behind a firewall (NAT).
 67* [XEP-0163: Personal Eventing Protocol](http://xmpp.org/extensions/xep-0163.html) for avatars and OMEMO.
 68* [XEP-0191: Blocking command](http://xmpp.org/extensions/xep-0191.html) lets you blacklist spammers or block contacts
 69  without removing them from your roster.
 70* [XEP-0198: Stream Management](http://xmpp.org/extensions/xep-0198.html) allows XMPP to survive small network outages and
 71  changes of the underlying TCP connection.
 72* [XEP-0280: Message Carbons](http://xmpp.org/extensions/xep-0280.html) which automatically syncs the messages you send to
 73  your desktop client and thus allows you to switch seamlessly from your mobile
 74  client to your desktop client and back within one conversation.
 75* [XEP-0237: Roster Versioning](http://xmpp.org/extensions/xep-0237.html) mainly to save bandwidth on poor mobile connections
 76* [XEP-0313: Message Archive Management](http://xmpp.org/extensions/xep-0313.html) synchronize message history with the
 77  server. Catch up with messages that were sent while Conversations was
 78  offline.
 79* [XEP-0352: Client State Indication](http://xmpp.org/extensions/xep-0352.html) lets the server know whether or not
 80  Conversations is in the background. Allows the server to save bandwidth by
 81  withholding unimportant packages.
 82* [XEP-0363: HTTP File Upload](http://xmpp.org/extensions/xep-0363.html) allows you to share files in conferences
 83  and with offline contacts.
 84
 85## FAQ
 86
 87### General
 88
 89#### How do I install Conversations?
 90
 91Conversations is entirely open source and licensed under GPLv3. So if you are a
 92software developer you can check out the sources from GitHub and use Gradle to
 93build your apk file.
 94
 95The more convenient way — which not only gives you automatic updates but also
 96supports the further development of Conversations — is to buy the App in the
 97Google [Play Store](https://play.google.com/store/apps/details?id=eu.siacs.conversations&referrer=utm_source%3Dgithub).
 98
 99Buying the App from the Play Store will also give you access to our [beta test](#beta).
100
101#### I don't have a Google Account but I would still like to make a contribution
102
103I accept donations over PayPal, bank transfer and various crypto currencies. For donations via PayPal use the button below:
104
105[![Donate with PayPal](https://www.paypalobjects.com/en_US/i/btn/btn_donate_LG.gif)](https://www.paypal.me/ConversationsIM)
106
107**Disclaimer:** I'm not a huge fan of PayPal and their business policies. For
108larger contributions please get in touch with me beforehand and we can talk
109about bank transfer (SEPA).
110
111##### Crypto currencies
112
113Bitcoin: `3KAD8vew6tPZDjiUJNnZ3YUoUxrCEVNwFL`
114
115Bitcoin Cash: `16ABkXzYAwWz8Y5DcWFfbBRqL63g3hzEaU`
116
117Ether: `0x5c4e5239cd9c6f4a909e4e8361526e2e3c8ba9fa`
118
119#### How do I create an account?
120XMPP, 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 providers out there. One of those providers is our very own [conversations.im](https://account.conversations.im). If you don’t like to use *conversations.im* use a web search engine of your choice to find another provider. 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.
121
122##### Domain hosting
123Using your own domain not only gives you a more recognizable Jabber ID, it also gives you the flexibility to migrate your account between different XMPP providers. This is a good compromise between the responsibilities of having to operate your own server and the downsides of being dependent on a single provider.
124
125Learn more about [conversations.im Jabber/XMPP domain hosting](https://account.conversations.im/domain/). 
126
127##### Running your own
128If you already have a server somewhere and are willing and able to put the necessary work in you can run your own XMPP server.
129
130As of 2019 we recommend you use [ejabberd](https://ejabberd.im). The default configuration file already enables everything you need to pass the [Conversations Compliance Suite](https://compliance.conversations.im). Make sure your Linux distribution ships a fairly recent version.
131
132With a little bit of effort [Prosody](https://prosody.im) can be configured to support all necessary extensions as well. However you will have to rely on so called [Community Modules](https://modules.prosody.im/) of varying quality. Prosody can be interesting to people who like to modify their server and create / prototype own modules.
133
134Performance wise - for small deployments - both ejabberd and Prosody should be fine. 
135
136#### Where can I set up a custom hostname / port
137Conversations will automatically look up the SRV records for your domain name
138which can point to any hostname port combination. If your server doesn’t provide
139those please contact your admin and have them read
140[this](http://prosody.im/doc/dns#srv_records). If your server operator is unwilling
141to fix this you can enable advanced server settings in the expert settings of
142Conversations.
143
144#### I get 'Incompatible Server'
145
146As regular user you should be picking a different server. The server you selected
147is probably insecure and/or very old.
148
149If you are a server administrator you should make sure that your server provides
150either STARTTLS or [XEP-0368: SRV records for XMPP over TLS](https://xmpp.org/extensions/xep-0368.html).
151
152On rare occasions this error message might also be caused by a server not providing
153a login (SASL) mechanism that Conversations is able to handle. Conversations supports
154SCRAM-SHA1, PLAIN, EXTERNAL (client certs) and DIGEST-MD5.
155
156#### I get 'Bind failure'. What does that mean?
157
158Some Bind failures are transient and resolve themselves after a reconnect.
159
160When trying to connect to OpenFire the bind failure can be a permanent problem when the domain part of the Jabber ID entered in Conversations doesn’t match the domain the OpenFire server feels responsible for. For example OpenFire is configured to use the domain `a.tld` but the Jabber ID entered is `user@b.tld` where `b.tld` also points to the same host. During bind OpenFire tries to reassign the Jabber to `user@a.tld`. Conversations doesn’t like that.
161This can be fixed by creating a new account in Conversations that uses the Jabber ID `user@a.tld`. 
162
163Note: This is kind of a weird quirk in OpenFire. Most other servers would just throw a 'Server not responsible for domain' error instead of attempting to reassign the Jabber ID.
164
165Maybe you attempted to use the Jabber ID `test@b.tld` because `a.tld` doesn’t point to the correct host. In that case you might have to enable the extended connection settings in the expert settings of Conversations and set a host name.
166
167### I get 'Stream opening error'. What does that mean?
168
169In most cases this error is caused by ejabberd advertising support for TLSv1.3 but not properly supporting it. This can happen if the openssl version on the server already supports TLSv1.3 but the fast\_tls wrapper library used by ejabberd not (properly) support it. Upgrading fast\_tls and ejabberd or - theoretically - downgrading openssl should fix the issue. A work around is to explicity disable TLSv1.3 support in the ejabberd configuration. More information can be found on [this issue on the ejabberd issue tracker](https://github.com/processone/ejabberd/issues/2614).
170
171
172#### I’m getting this annoying permanent notification
173Starting with Conversations 2.3.6 Conversations releases distributed over the Google Play Store will display a permanent notification if you are running it on Android 8 and above. This is a rule that it is essentially enforced by the Google Play Store. (You won’t have the problem  of a *forced* foreground notification if you are getting your app from F-Droid.)
174
175However you can disable the notification via settings of the operating system. (Not settings in Conversations.)
176
177**The battery consumption and the entire behaviour of Conversations will remain the same (as good or as bad as it was before). Why is Google doing this to you? We have no idea.**
178
179##### Android &lt;= 7.1
180The foreground notification is still controlled over the expert settings within Conversations as it always has been. Whether or not you need to enable it depends on how aggressive the non-standard 'power saving' features are that your phone vendor has built into the operating system.
181
182##### Android 8.x
183Long press the permanent notification and disable that particular type of notification by moving the slider to the left. This will make the notification disappear but create another notification (this time created by the operating system itself.) that will complain about Conversations (and other apps) using battery. Starting with Android 8.1 you can disable that notification again with the same method described above.
184
185##### Android 9.0+
186Long press the permanent notification and press the info `(i)` button to get into the App info screen. In that screen touch the 'Notification' entry. In the next screen remove the checkbox for the 'Foreground service' entry. 
187
188#### How do XEP-0357: Push Notifications work?
189You need to be running the Play Store version of Conversations and your server needs to support push notifications.¹ Because *Google’s Firebase Cloud Messaging (FCM)* are tied with an API key to a specific app your server can not initiate the push message directly. Instead your server will send the push notification to the [Conversations App server](https://github.com/iNPUTmice/p2) (operated by us) which then acts as a proxy and initiates the push message for you. The push message sent from our App server through FCM doesn’t contain any personal information. It is just an empty message which will wake up your device and tell Conversations to reconnect to your server. The information sent from your server to our App server depends on the configuration of your server but can be limited to your account name. (In any case the Conversations App server won't redirect any information through FCM even if your server sends this information.)
190
191In summary Google will never get hold of any personal information besides that *something* happened. (Which doesn’t even have to be a message but can be some automated event as well.) We - as the operator of the App server - will just get hold of your account name (without being able to tie this to your specific device).
192
193If you don’t want this simply pick a server which does not offer Push Notifications or build Conversations yourself without support for push notifications. (This is available via a gradle build flavor.) Non-play store source of Conversations like the Amazon App store will also offer a version without push notifications. Conversations will just work as before and maintain its own TCP connection in the background.
194
195You can find a detailed description of how your server, the app server and FCM are interacting with each other in the [README](https://github.com/iNPUTmice/p2/blob/master/README.md) of the Conversations App Server.
196
197 ¹ Your server only needs to support the server side of [XEP-0357: Push Notifications](http://xmpp.org/extensions/xep-0357.html). If you use the Play Store version you do **not** need to run your own app server. The server modules are called *mod_cloud_notify* on Prosody and *mod_push* on ejabberd.
198
199
200#### But why do I need a permanent notification if I use Google Push?
201FCM (Google Push) allows an app to wake up from *Doze* which is (as the name suggests) a hibernation feature of the Android operating system that cuts the network connection and also reduces the number of times the app is allowed to wake up (to ping the server for example). The app can ask to be excluded from doze. Non push variants of the app (from F-Droid or if the server doesn’t support it) will do this on first start up. So if you get exemption from *Doze*, or if you get regular push events sent to you, Doze should not pose a threat to Conversatons working properly. But even with *Doze* the app is still open in the background (kept in memory); it is just limited in the actions it can do. Conversations needs to stay in memory to hold certain session state (online status of contacts, join status of group chats, …). However with Android 8 Google changed all of this again and now an App that wants to stay in memory needs to have a foreground service which is visible to the user via the annoying notification. But why does Conversations need to hold that state? XMPP is a stateful protocol that has a lot of per-session information; packets need to be counted, presence information needs to be held, some features like Message Carbons get activated once per session, MAM catchup happens once, service discovery happens only once; the list goes on. When Conversations was created in early 2014 none of this was a problem because apps were just allowed to stay in memory. Basically every XMPP client out there holds that information in memory because it would be a lot more complicated trying to persist it to disk. An entire rewrite of Conversations in the year 2019 would attempt to do that and would probably succeed however it would require exactly that; a complete rewrite which is not feasible right now. That’s by the way also the reason why it is difficult to write an XMPP client on iOS. Or more broadly put this is also the reason why other protocols are designed as or migrated to stateless protocols (often based on HTTP); take for example the migration of IMAP to [JMAP](https://jmap.io/).
202
203#### Conversations doesn’t work for me. Where can I get help?
204
205You can join our conference room on `conversations@conference.siacs.eu`.
206A lot of people in there are able to answer basic questions about the usage of
207Conversations or can provide you with tips on running your own XMPP server. If
208you found a bug or your app crashes please read the Developer / Report Bugs
209section of this document.
210
211#### I need professional support with Conversations or setting up my server
212
213I'm available for hire. Contact information can be found on [my website](https://gultsch.de).
214
215#### How does the address book integration work?
216
217The address book integration was designed to protect your privacy. Conversations
218neither uploads contacts from your address book to your server nor fills your
219address book with unnecessary contacts from your online roster. If you manually
220add a Jabber ID to your phones address book Conversations will use the name and
221the profile picture of this contact. To make the process of adding Jabber IDs to
222your address book easier you can click on the profile picture in the contact
223details within Conversations. This will start an "add to address book" intent
224with the JID as the payload. This doesn't require Conversations to have write
225permissions on your address book but also doesn't require you to copy/paste a
226JID from one app to another.
227
228#### I get 'delivery failed' on my messages
229
230If you get delivery failed on images it's probably because the recipient lost
231network connectivity during reception. In that case you can try it again at a
232later time.
233
234For text messages the answer to your question is a little bit more complex.
235When you see 'delivery failed' on text messages, it is always something that is
236being reported by the server. The most common reason for this is that the
237recipient failed to resume a connection. When a client loses connectivity for a
238short time the client usually has a five minute window to pick up that
239connection again. When the client fails to do so because the network
240connectivity is out for longer than that all messages sent to that client will
241be returned to the sender resulting in a delivery failed.
242
243Instead of returning a message to the sender both ejabberd and prosody have the
244ability to store messages in offline storage when the disconnecting client is
245the only client. In prosody this is available via an extra module called
246```mod_smacks_offline```. In ejabberd this is available via some configuration
247settings.
248
249Other less common reasons are that the message you sent didn't meet some
250criteria enforced by the server (too large, too many). Another reason could be
251that the recipient is offline and the server doesn't provide offline storage.
252
253Usually you are able to distinguish between these two groups in the fact that
254the first one happens always after some time and the second one happens almost
255instantly.
256
257#### Where can I see the status of my contacts? How can I set a status or priority?
258
259Statuses are a horrible metric. Setting them manually to a proper value rarely
260works because users are either lazy or just forget about them. Setting them
261automatically does not provide quality results either. Keyboard or mouse
262activity as indicator for example fails when the user is just looking at
263something (reading an article, watching a movie). Furthermore automatic setting
264of status always implies an impact on your privacy (are you sure you want
265everybody in your contact list to know that you have been using your computer at
2664am‽).
267
268In the past status has been used to judge the likelihood of whether or not your
269messages are being read. This is no longer necessary. With Chat Markers
270(XEP-0333, supported by Conversations since 0.4) we have the ability to **know**
271whether or not your messages are being read.  Similar things can be said for
272priorities. In the past priorities have been used (by servers, not by clients!)
273to route your messages to one specific client. With carbon messages (XEP-0280,
274supported by Conversations since 0.1) this is no longer necessary. Using
275priorities to route OTR messages isn't practical either because they are not
276changeable on the fly. Metrics like last active client (the client which sent
277the last message) are much better.
278
279Unfortunately these modern replacements for legacy XMPP features are not widely
280adopted. However Conversations should be an instant messenger for the future and
281instead of making Conversations compatible with the past we should work on
282implementing new, improved technologies and getting them into other XMPP clients
283as well.
284
285Making these status and priority optional isn't a solution either because
286Conversations is trying to get rid of old behaviours and set an example for
287other clients.
288
289#### Translations
290Translations are managed on [Transifex](https://www.transifex.com/projects/p/conversations/).
291If you want to become a translator  Please register on transifex, apply to join
292the translation team and then step by our group chat on
293[conversations@conference.siacs.eu](https://conversations.im/j/conversations@conference.siacs.eu)
294and introduce yourself to `iNPUTmice` so he can approve your join request.
295
296#### How do I backup / move Conversations to a new device?
297On the one hand Conversations supports Message Archive Management to keep a server side history of your messages so when migrating to a new device that device can display your entire history. However that does not work if you enable OMEMO due to its forward secrecy. (Read [The State of Mobile XMPP in 2016](https://gultsch.de/xmpp_2016.html) especially the section on encryption.)
298
299As of version 2.4.0 an integrated Backup & Restore function will help with this, go to Settings &#8594; Expert settings &#8594; Create backup. A notification will pop-up during the creation process that will announce you when it's ready. After the files, one for each account, are created, you can move the **Conversations** folder *(if you want your old media files too)* or only the **Conversations/Backup** folder *(for OMEMO keys and history only)* to your new device (or to a storage place) where a freshly installed Conversations can restore each account. Don't forget to enable the accounts after a succesful restore.
300
301This backup method will include your OMEMO keys. Due to forward secrecy you will not be able to recover messages sent and received between creating the backup and restoring it. If you have a server side archive (MAM) those messages will be retrieved but displayed as *unable to decrypt*. For technical reasons you might also lose the first message you either sent or receive after the restore; for each conversation you have. This message will then also show up as *unable to decrypt*, but this will automatically recover itself as long as both participants are on Conversations 2.3.11+. Note that this doesn’t happen if you just transfer to a new phone and no messages have been exchanged between backup and restore.
302
303In the vast, vast majority of cases you won’t have to manually delete OMEMO keys or do anything like that. Conversations only introduced the offical backup feature in 2.4.0 after making sure the *OMEMO self healing* mechanism introduced in 2.3.11 works fine.
304
305**WARNING**: Be sure to know your accounts passwords or find ways to reset them **before** doing the backup as the files are encrypted using those passwords and the Restore process will ask for them.  
306**WARNING**: Do not use the restore backup feature in an attempt to clone (run simultaneously) an installation. Restoring a backup is only meant for migrations or in case you’ve lost the original device.
307
308#### Conversations is missing a certain feature
309
310I'm open for new feature suggestions. You can use the [issue tracker][issues] on
311GitHub.  Please take some time to browse through the issues to see if someone
312else already suggested it. Be assured that I read each and every ticket. If I
313like it I will leave it open until it's implemented. If I don't like it I will
314close it (usually with a short comment). If I don't comment on an feature
315request that's probably a good sign because this means I agree with you.
316Commenting with +1 on either open or closed issues won't change my mind, nor
317will it accelerate the development.
318
319#### You closed my feature request but I want it really really badly
320
321Just write it yourself and send me a pull request. If I like it I will happily
322merge it if I don't at least you and like minded people get to enjoy it.
323
324#### I need a feature and I need it now!
325
326I am available for hire. Contact me via XMPP: `inputmice@siacs.eu`
327
328### Security
329
330#### Why are there two end-to-end encryption methods and which one should I choose?
331
332* 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 not widely support and is currently implemented only [by a handful of clients](https://omemo.top).
333* OpenPGP (XEP-0027) is a very old encryption method that has some advantages over OMEMO but should only be used by people who know what they are doing.
334
335#### How do I use OpenPGP
336
337Before you continue reading you should note that the OpenPGP support in
338Conversations is experimental. This is not because it will make the app unstable
339but because the fundamental concepts of PGP aren't ready for widespread use.
340The way PGP works is that you trust Key IDs instead of JID's or email addresses.
341So in theory your contact list should consist of Public-Key-IDs instead of
342JID's. But of course no email or XMPP client out there implements these
343concepts. Plus PGP in the context of instant messaging has a couple of
344downsides: It is vulnerable to replay attacks and it is rather verbose.
345
346To use OpenPGP you have to install the open source app
347[OpenKeychain](http://www.openkeychain.org) and then long press on the account in
348manage accounts and choose renew PGP announcement from the contextual menu.
349
350#### OMEMO is grayed out. What do I do?
351OMEMO is only available in 1:1 chats and private (members-only, non-anonymous) group chats. Encrypting public group chats makes little to no sense since anyone (including a hypothetical attacker) can join and a user couldn’t possibily verify all participants anyway. Furthermore for a lot of public group chat it is desirable to give new comers access to the full history.
352
353#### OMEMO doesn’t work. I get a 'Something went wrong' message in the 'Trust OMEMO Fingerprints' screen.
354OMEMO has two requirements: Your server and the server of your contact need to support PEP. Both of you can verify that individually by opening your account details and selecting ```Server info``` from the menu. The appearing table should list PEP as available. The second requirement is that the initial sender needs to have access to the published key material. This can either be achieved by having mutual presence subscription (you can verify that by opening the contact details and see if both check boxes *Send presence updates* and *Receive presence updates* are checked) or by using a server that makes the public key material accessible to anyone. In the [Compliance Tester](https://compliance.conversations.im) this is indicated by the 'OMEMO' feature. Since it is very common that the first messages are exchanged *before* adding each other to the contact list it is desirable to use servers that have 'OMEMO support'.
355
356#### How does the encryption for group chats work?
357
358##### OMEMO
359
360OMEMO encryption works only in private (members only) conferences that are non-anonymous. Non-anonymous (being able to discover the real JID of other participants) is a technical requirement to discover the key material. Members only is a sort of arbitrary requirement imposed by Conversations. (see 'OMEMO is grayed out')
361
362The server of all participants need to pass the OMEMO [Compliance Test](https://conversations.im/compliance/).
363In other words they either need to run Ejabberd 18.01+ or Prosody 0.11+.
364
365(Alternatively it would also work if all participants had each other in their contact list; But that rarely is the case in larger group chats.)
366
367The owner of a conference can make a public conference private by going into the conference
368details and hit the settings button (the one with the gears) and select both *private* and
369*members only*.
370
371##### OpenPGP
372
373Every participant has to announce their OpenPGP key (see answer above).
374If you would like to send encrypted messages to a conference you have to make
375sure that you have every participant's public key in your OpenKeychain.
376Right now there is no check in Conversations to ensure that.
377You have to take care of that yourself. Go to the conference details and
378touch every key id (The hexadecimal number below a contact). This will send you
379to OpenKeychain which will assist you on adding the key.  This works best in
380very small conferences with contacts you are already using OpenPGP with. This
381feature is regarded experimental. Conversations is the only client that uses
382XEP-0027 with conferences. (The XEP neither specifically allows nor disallows
383this.)
384
385#### What is Blind Trust Before Verification / why are messages marked with a red lock?
386
387Read more about the concept on https://gultsch.de/trust.html
388
389#### What happened to OTR support?
390OTR was removed because it was highly unreliable. It didn’t work with multiple devices and was never really specified to work with XMPP. The codebase was a mess (There was an HTML parser in there for crying out loud to deal with the garbage some OTR clients would send.) Verification was implemented in a non-blocking way. It would tell you if the current session was using an unknown fingerprint but it didn’t actively stopped you from sending messages until you have confirmed the new fingerprint. (Like Conversations would do now with BTBV after verification or when BTBV is turned off.) Considering the previous points there was little to no desire from my point to fix this potential security issue or clean up the code base. Another reason for the removal was that people would use it *accidentally* even to communicate between two Conversations clients because they read somewhere that OTR is good.
391
392OTR is still available in [Conversations Legacy](https://github.com/siacs/Conversations/tree/legacy).
393
394### What clients do I use on other platforms
395There are XMPP Clients available for all major platforms.
396#### Windows / Linux
397For your desktop computer we recommend that you use [Gajim](https://gajim.org). You need to install the plugins `OMEMO`, `HTTP Upload` and `URL image preview` to get the best compatibility with Conversations. Plugins can be installed from within the app.
398#### iOS
399Unfortunately we don‘t have a recommendation for iPhones right now. There are two clients available [ChatSecure](https://chatsecure.org/) and [Monal](https://monal.im/). Both with their own pros and cons.
400
401
402### Development
403
404<a name="beta"></a>
405#### Beta testing
406If you bought the App on [Google Play](https://play.google.com/store/apps/details?id=eu.siacs.conversations)
407you can get access to the the latest beta version by signing up using [this link](https://play.google.com/apps/testing/eu.siacs.conversations).
408
409#### How do I build Conversations
410
411Make sure to have ANDROID_HOME point to your Android SDK. Use the Android SDK Manager to install missing dependencies.
412
413    git clone https://github.com/siacs/Conversations.git
414    cd Conversations
415    ./gradlew assembleConversationsFreeSystemDebug
416
417There are two build flavors available. *free* and *playstore*. Unless you know what you are doing you only need *free*.
418
419
420[![Build Status](https://travis-ci.org/siacs/Conversations.svg?branch=development)](https://travis-ci.org/siacs/Conversations)
421
422#### How do I update/add external libraries?
423
424If the library you want to update is in Maven Central or JCenter (or has its own
425Maven repo), add it or update its version in `build.gradle`. If the library is
426in the `libs/` directory, you can update it using a subtree merge by doing the
427following (using `minidns` as an example):
428
429    git remote add minidns https://github.com/rtreffer/minidns.git
430    git fetch minidns
431    git merge -s subtree minidns master
432
433To add a new dependency to the `libs/` directory (replacing "name", "branch" and
434"url" as necessary):
435
436    git remote add name url
437    git merge -s ours --no-commit name/branch
438    git read-tree --prefix=libs/name -u name/branch
439    git commit -m "Subtree merged in name"
440
441#### How do I debug Conversations
442
443If something goes wrong Conversations usually exposes very little information in
444the UI (other than the fact that something didn't work). However with adb
445(android debug bridge) you can squeeze some more information out of Conversations.
446These information are especially useful if you are experiencing trouble with
447your connection or with file transfer.
448
449To use adb you have to connect your mobile phone to your computer with an USB cable
450and install `adb`. Most Linux systems have prebuilt packages for that tool. On
451Debian/Ubuntu for example it is called `android-tools-adb`.
452
453Furthermore you might have to enable 'USB debugging' in the Developer options of your
454phone. After that you can just execute the following on your computer:
455
456    adb -d logcat -v time -s conversations
457
458If need be there are also some Apps on the PlayStore that can be used to show the logcat
459directly on your rooted phone. (Search for logcat). However in regards to further processing
460(for example to create an issue here on Github) it is more convenient to just use your PC.
461
462#### I found a bug
463
464Please report it to our [issue tracker][issues]. If your app crashes please
465provide a stack trace. If you are experiencing misbehavior please provide
466detailed steps to reproduce. Always mention whether you are running the latest
467Play Store version or the current HEAD. If you are having problems connecting to
468your XMPP server your file transfer doesn’t work as expected please always
469include a logcat debug output with your issue (see above).
470
471[issues]: https://github.com/siacs/Conversations/issues