Open Source Java Messaging Platforms

Telegram is a wonderful and private messaging app that offers simple, fast, secure and synced messaging for all your devices. It delivers messages faster than any other application; cloud-based so you can access your messages from any device; and very secure, with messages heavily encrypted and could even self-destruct. Telegram is simple and fun to use, with powerful photo and video editing tools as well as an open sticker/GIF platform to let you express yourself fully. It’s also incredibly powerful. Whether you’re setting up a group chat for up to 200,000 members or sharing large videos or documents, Telegram is up to the task. Best of all it’s completely free and open source, with no ads or subscription fees.

Fall in love with texting all over again with QKSMS! QKSMS is a beautiful, simple and customizable open source replacement to the stock messaging app on Android. It's got a clean, clutter-free intuitive design that lets you focus on what matters, plus millions of colors to choose from to make the theme of the entire app truly your own. QKSMS has some powerful features, including photo sharing, group chat, conversation blocking, message backup and restore and more. It's got everything you need from a text messaging app, plus all the fun features that make for a great text messaging experience. Simply put, QKSMS makes texting magical again, just the way it should be!

Signal Server is the official backend server component that supports the Signal Private Messenger ecosystem on Android, iOS, and desktop platforms, serving as the trusted message relay, contact discovery, and push notification hub while the clients handle end-to-end encryption. Built in Java and licensed under the AGPL-3.0 license, this server software handles protocols for delivering encrypted messages, synchronizing user metadata like public keys and push tokens, and providing REST and service APIs for the client apps to interact with. Although cryptographic operations and message confidentiality are managed by the client side using the Signal Protocol, the server ensures message routing, user registration, and group updates without having access to the decrypted contents. Its codebase is public to ensure transparency and auditability for a security-focused community willing to inspect how message metadata and delivery mechanisms are implemented.

This open-source library allows you to integrate Facebook into your Android app. Integrate your Android app with Facebook to build engaging social apps by using the Facebook SDK for Android. To learn more about using Facebook development tools. The current version of the Facebook SDK for Android is version 11.2.0 and requires the Android API 15. Code and samples for the Facebook SDK for Android are available on GitHub. A secure and convenient way for people to log into your app or website by using their Facebook credentials. Enable people to post to Facebook from your app. People can share, send a message, and share to stories. Understand people's actions in your app and measure the effectiveness of your Mobile App Ads. Get data in and out of Facebook's social graph, query data, post stories, upload photos and perform other tasks.

Riot Android is the original Android client for the Matrix network — a decentralized, secure communication protocol — that enables users to send end-to-end encrypted messages, join rooms, conduct voice and video calls, and interact across federated communities without relying on centralized servers. As the predecessor to Element X, Riot Android laid the groundwork for mobile access to Matrix while providing advanced features like threaded replies, rich media handling, room moderation, and custom notification controls. It integrates tightly with Android’s native platform capabilities, offering background sync, push notifications, and account management while keeping user cryptographic keys secure on the device for privacy. Users appreciate Riot’s ability to join public or private communities hosted across different Matrix servers, making it useful for both personal and organizational communication with interoperability at its core.

EZ Intranet Messenger is designed to work within a LAN segment, without the presence of centralized server. Its primary goal is to provide instant messaging service, along with online status notification, file transmission, and real time public chat.

JML is a java Msn Messenger library that supports MSNP8-MSNP15. It is optimized for multiple users and is intended to be very easy to follow and use.

Kraken is a continuation of the Openfire IM Gateway plugin, but in a way that works for any XMPP server. It provides a way for XMPP users to log into, and communicate through, their legacy IM accounts such as AIM, ICQ, MSN, Yahoo, and friends.

Smoke is an encrypting chat messenger for Android written in Java. Please read the Web site for more information: https://textbrowser.github.io/smoke/ (original, current) https://www.amazon.com/dp/3752691999/ https://smokeappope.sourceforge.io/ (old, third party archive) Smoke App OPE - Open Personal Encryption Download Android APK Installer: https://sourceforge.net/projects/smokeappope/files/ Smoke Source: https://github.com/textbrowser/smoke SmokeStack Source: https://github.com/textbrowser/smokestack (Android) https://github.com/textbrowser/spot-on (Desktop) Smoke appears to be one of the first projects with an open source mobile encrypting chat server., an decentralized and easily-configurable chat server. Smoke is known as the first mobile McEliece Messenger: https://tarnkappe.info/artikel/english/mceliece-messaging-smoke-crypto-chat-the-first-mobile-mceliece-messenger-published-as-a-stable-prototype-worldwide-279847.html

This is a java based LAN messenger with file transfer support, chat and even a simple LAN game

Jalk: an instant messenging system for small work groups - written in Java (--> OS independent) - clients can reside behind a firewall (incl. NAT) - encrypted comunication - participants can see the others typing and correcting (like unix talk)

All in one social network browser app provides easy access to all social networks and other useful applications in one application which makes it easy to share your most recently used apps. It includes applications such as G Mail, Messenger, Whats App, Google Drive, Google Slides, Google Duo and much more. Simultaneously it lets you access all the application. Disclaimer:- All websites featured in the app have gone through a permission process.

Does not work because there is no master server! A P2P Messenger which uses JXTA. It provides secure RSA/AES end-to-end encryption and VoIP-Capabilities.

JIM is a cross-platform instant messenger. Based on TCP/IP protocol. Supports conferencing as well as private messages.

JIMO(Java-based Instant Messenger One), supports multiple protocols via services, including AIM, MSN, Yahoo, IRC. It is flexible through its plugin architecture, with an intelligent agent, Chatbot.

Jasim (Just Another Simple Instant Messenger) is a simple instant messenger program written entirely in Java. Jasim will feature a protocol that can be extended through plug-ins. It will have a client library with full API documentation so that anyone wh

Underground IM is a free Java Instant Messaging solution. Both a client and a server are available. Underground IM is open source software distributed free of charge under the terms of the GNU General Public License. *Public Server: 64.94.101.216:5632

A simple an easy to use Instant Messenger application to use on networked computers. Minimal to no setup required.

AJIM is a pure JAVA instant messenger software. It uses the Smack API for the XMPP (Jabber) protocol.

Azonto is a Cross-Platform Mobile Messaging Application that allows users to share images, songs, videos, create and add each other to groups. It is for the trendy who wants to be on top of the mobile messaging game.

This web service developped in Java provides WebForum services on the IMAP4/POP3 protocol : you don't need database, and common messaging tool like Netscape Messenger or Outlook permits to create/delete new forum and to moderate messages.

A secure alternative to the BlackBerry Messenger.

Briar is a messaging app designed for activists, journalists, and anyone else who needs a safe, easy and robust way to communicate. Unlike traditional messaging tools such as email, Twitter or Telegram, Briar doesn't rely on a central server - messages are synchronized directly between the users' devices. If the Internet's down, Briar can sync via Bluetooth or Wi-Fi, keeping the information flowing in a crisis. If the Internet's up, Briar can sync via the Tor network, protecting users and their relationships from surveillance.

CIM(CROSS-IM)A developer-oriented system, provides components to help developers build their own distributed instant messaging system that can be a horizontal scaling IM. CIM is an IM Instant messaging system, can be applied as a message push middleware. IOT Message transparent transmission middleware in massive connection scenarios. Provides flexible horizontal expansion and contraction according to the actual situation. The server automatically removes offline clients. Client reconnects automatically. You can use Google Protocol Bufferefficient codec. Its protocol supports message encryption. Store routing information, account information, online status, etc. of each client. Message routing server; used to process message routing, message forwarding, user login, user offline, and some operational tools (obtaining the number of online users, etc.).