OTR -- Off-the-Record

[Costas]

outdated
https://otr.im/clients.html

cant get it work
https://play.google.com/store/apps/details?id=org.frozenbox.frozenchat&hl=en

went paid (latest technology)
https://github.com/siacs/Conversations
last free - https://f-droid.org/en/packages/eu.siacs.conversations/
 
 

Delta Chat
Is a project that aims to create a messaging app that is completely compatible to the existing e-mail infrastructure, implementation of Autocrypt
https://delta.chat download by f-droid
use mail from - https://dismail.de/register.html (mail portal https://webmail.dismail.de/)
 

Riot.im
https://play.google.com/store/apps/details?id=im.vector.alpha
https://f-droid.org/packages/im.vector.alpha/
homepage
 

---

 
https://guardianproject.info/releases/

https://guardianproject.info/howto/chatsecurely/

https://github.com/guardianproject/ChatSecureAndroid
 

---

 

Since 2004 XMPP is the IETF-approved instant messaging and presence protocol. XMPP is based on the Jabber protocol that evolves since 1998. Basically programming Jabber software today means programming XMPP compliant software. XMPP is the new name (Google Talk used to run on this), Jabber the old.

online
https://chat.frozenbox.org/inverse/ based on https://conversejs.org + https://inverse.chat/

XMPP Servers - https://xmpp.org/software/servers.html
XMPP Clients - https://xmpp.org/software/clients.html

Public XMPP servers - https://list.jabber.at/
stable servers - https://jabber.hot-chilli.net/ or http://yam.im
 

---

 
create your own XMPP server with :
-https://www.process-one.net/en/ejabberd/   tutorial
-https://prosody.im/
-http://www.igniterealtime.org/projects/openfire/index.jsp

Comparison of XMPP server software
 

---

 
WhatApp uses a variation of XMPP for its popular chat service - https://github.com/mgp25/Chat-API/wiki/FunXMPP-Protocol

#otr