@ -337,8 +337,8 @@ _See also: [Comparison of CalDAV and CardDAV implementations - Wikipedia](https:
- [Apprise](https://github.com/caronc/apprise) - Apprise allows you to send a notification to almost all of the most popular notification services available to us today such as: Telegram, Discord, Slack, Amazon SNS, Gotify, etc. `MIT``Python/Docker`
- [Apprise](https://github.com/caronc/apprise) - Apprise allows you to send a notification to almost all of the most popular notification services available to us today such as: Telegram, Discord, Slack, Amazon SNS, Gotify, etc. `MIT``Python/Docker`
- [BluetoothCommunicatorExample](https://github.com/niedev/BluetoothCommunicatorExample) - Bluetooth LE chat app to communicate between android devices with P2P architecture. ([Clients](https://github.com/niedev/RTranslator)) `Apache-2.0``Java`
- [BluetoothCommunicatorExample](https://github.com/niedev/BluetoothCommunicatorExample) - Bluetooth LE chat app to communicate between android devices with P2P architecture. ([Clients](https://github.com/niedev/RTranslator)) `Apache-2.0``Java`
- [Chatwoot](https://www.chatwoot.com) - Self-hosted customer communication platform, an alternative to Intercom & Zendesk. ([Source Code](https://github.com/chatwoot/chatwoot)) `MIT``Ruby`
- [Chatwoot](https://www.chatwoot.com) - Self-hosted customer communication platform, an alternative to Intercom & Zendesk. ([Source Code](https://github.com/chatwoot/chatwoot)) `MIT``Ruby/Docker/K8S`
- [Chitchatter](https://chitchatter.im/) - A peer-to-peer chat app that is serverless, decentralized, and ephemeral. ([Source Code](https://github.com/jeremyckahn/chitchatter)) `GPL-2.0``Nodejs`
- [Chitchatter](https://chitchatter.im/) - A peer-to-peer chat app that is serverless, decentralized, and ephemeral. ([Source Code](https://github.com/jeremyckahn/chitchatter)) `GPL-2.0``Nodejs`
- [Conduit](https://conduit.rs/) - A simple, fast, and reliable chat server powered by Matrix. ([Source Code](https://gitlab.com/famedly/conduit)) `Apache-2.0``Rust`
- [Conduit](https://conduit.rs/) - A simple, fast, and reliable chat server powered by Matrix. ([Source Code](https://gitlab.com/famedly/conduit)) `Apache-2.0``Rust`
- [Darkwire.io](https://github.com/darkwire/darkwire.io) - End-to-end encrypted instant web chat. `MIT``Nodejs`
- [Darkwire.io](https://github.com/darkwire/darkwire.io) - End-to-end encrypted instant web chat. `MIT``Nodejs`
@ -348,43 +348,43 @@ _See also: [Comparison of CalDAV and CardDAV implementations - Wikipedia](https:
- [Enigma Reloaded](https://github.com/enigma-reloaded/enigma-reloaded) - DIY Message and file encryption for any platform. `GPL-3.0``Javascript`
- [Enigma Reloaded](https://github.com/enigma-reloaded/enigma-reloaded) - DIY Message and file encryption for any platform. `GPL-3.0``Javascript`
- [Freenet](https://freenetproject.org/index.html) - Anonymously share files, browse and publish _freesites_ (web sites accessible only through Freenet) and chat on forums. ([Source Code](https://github.com/freenet/fred)) `GPL-2.0``Java`
- [Freenet](https://freenetproject.org/index.html) - Anonymously share files, browse and publish _freesites_ (web sites accessible only through Freenet) and chat on forums. ([Source Code](https://github.com/freenet/fred)) `GPL-2.0``Java`
- [Gotify](https://gotify.net/) - Self-hosted notification server with Android and CLI clients, similar to PushBullet. ([Source Code](https://github.com/gotify/server), [Clients](https://github.com/gotify/android)) `MIT``Go`
- [Gotify](https://gotify.net/) - Self-hosted notification server with Android and CLI clients, similar to PushBullet. ([Source Code](https://github.com/gotify/server), [Clients](https://github.com/gotify/android)) `MIT``Go/Docker`
- [Hawkpost](https://hawkpost.co) - HawkPost is a web app that lets you create unique links that you can share with a person that desires to send you important information but doesn't know how to encrypt it. The message is encrypted in their browser and sent to your email address. ([Source Code](https://github.com/whitesmith/hawkpost)) `MIT``Python`
- [Hawkpost](https://hawkpost.co) - HawkPost is a web app that lets you create unique links that you can share with a person that desires to send you important information but doesn't know how to encrypt it. The message is encrypted in their browser and sent to your email address. ([Source Code](https://github.com/whitesmith/hawkpost)) `MIT``Python/Docker`
- [Jam](https://jamshelf.com/) - Jam is an open source alternative to Clubhouse: private audio chat rooms to talk to friends and family. ([Demo](https://jam.systems/), [Source Code](https://github.com/jam-systems/jam)) `AGPL-3.0``Docker/Nodejs`
- [Jam](https://jamshelf.com/) - Jam is an open source alternative to Clubhouse: private audio chat rooms to talk to friends and family. ([Demo](https://jam.systems/), [Source Code](https://github.com/jam-systems/jam)) `AGPL-3.0``Docker/Nodejs`
- [Jami](https://jami.net/) - Free and universal communication platform which preserves the user's privacy and freedoms (formerly GNU Ring). ([Source Code](https://git.jami.net/savoirfairelinux/jami-project)) `GPL-3.0``C++`
- [Jami](https://jami.net/) - Free and universal communication platform which preserves the user's privacy and freedoms (formerly GNU Ring). ([Source Code](https://git.jami.net/savoirfairelinux/jami-project)) `GPL-3.0``C++`
- [KChat](https://github.com/php-kchat/kchat) - PHP Based Live Chat Application. `Apache-2.0``PHP`
- [KChat](https://github.com/php-kchat/kchat) - PHP Based Live Chat Application. `Apache-2.0``PHP`
- [Live Helper Chat](https://livehelperchat.com/) - Live Support chat for your website. ([Source Code](https://github.com/LiveHelperChat/livehelperchat)) `Apache-2.0``PHP`
- [Live Helper Chat](https://livehelperchat.com/) - Live Support chat for your website. ([Source Code](https://github.com/LiveHelperChat/livehelperchat)) `Apache-2.0``PHP`
- [Mattermost](https://mattermost.org/) - Open-source, on-prem Slack-alternative. It can be integrated with Gitlab. ([Source Code](https://github.com/mattermost/mattermost-server)) `AGPL-3.0/Apache-2.0``Go`
- [Mattermost](https://mattermost.org/) - Open-source, on-prem Slack-alternative. It can be integrated with Gitlab. ([Source Code](https://github.com/mattermost/mattermost-server)) `AGPL-3.0/Apache-2.0``Go/Docker/K8S`
- [Mibew](https://mibew.org) - Mibew Messenger is an open-source live support application written in PHP and MySQL. It enables one-on-one chat assistance in real-time directly from your website. ([Demo](https://mibew.org/demo2), [Source Code](https://github.com/Mibew/mibew)) `Apache-2.0``PHP`
- [Mibew](https://mibew.org) - Mibew Messenger is an open-source live support application written in PHP and MySQL. It enables one-on-one chat assistance in real-time directly from your website. ([Demo](https://mibew.org/demo2), [Source Code](https://github.com/Mibew/mibew)) `Apache-2.0``PHP`
- [Notifo](https://github.com/notifo-io/notifo) - Multichannel notification server with support for Email, Mobile Push, Web Push, SMS, messaging and a javascript plugin. `MIT``C#`
- [Notifo](https://github.com/notifo-io/notifo) - Multichannel notification server with support for Email, Mobile Push, Web Push, SMS, messaging and a javascript plugin. `MIT``C#`
- [ntfy](https://ntfy.sh/) - Push notifications to phone or desktop using HTTP PUT/POST, with Android app, CLI and web app, similar to Pushover and Gotify. ([Demo](https://ntfy.sh/app), [Source Code](https://github.com/binwiederhier/ntfy), [Clients](https://github.com/binwiederhier/ntfy-android)) `Apache-2.0/GPL-2.0``Go`
- [ntfy](https://ntfy.sh/) - Push notifications to phone or desktop using HTTP PUT/POST, with Android app, CLI and web app, similar to Pushover and Gotify. ([Demo](https://ntfy.sh/app), [Source Code](https://github.com/binwiederhier/ntfy), [Clients](https://github.com/binwiederhier/ntfy-android)) `Apache-2.0/GPL-2.0``Go/Docker/K8S`
- [OTS](https://ots.fyi/) - One-Time-Secret sharing platform with a symmetric 256bit AES encryption in the browser. ([Source Code](https://github.com/Luzifer/ots)) `Apache-2.0``Go`
- [OTS](https://ots.fyi/) - One-Time-Secret sharing platform with a symmetric 256bit AES encryption in the browser. ([Source Code](https://github.com/Luzifer/ots)) `Apache-2.0``Go`
- [Papercups](https://papercups.io/) - An open source live customer chat web app written in Elixir. ([Demo](https://app.papercups.io/demo), [Source Code](https://github.com/papercups-io/papercups)) `MIT``Elixir`
- [Papercups](https://papercups.io/) - An open source live customer chat web app written in Elixir. ([Demo](https://app.papercups.io/demo), [Source Code](https://github.com/papercups-io/papercups)) `MIT``Elixir`
- [PushBits](https://github.com/pushbits/server) - Self-hosted notification server for relaying push notifications via Matrix, similar to PushBullet and Gotify. `ISC``Go`
- [PushBits](https://github.com/pushbits/server) - Self-hosted notification server for relaying push notifications via Matrix, similar to PushBullet and Gotify. `ISC``Go`
- [Rallly](https://rallly.co) - Rallly is an open-source alternative to Doodle that lets you create polls to vote on dates and times. ([Source Code](https://github.com/lukevella/Rallly)) `AGPL-3.0``Nodejs`
- [Rallly](https://rallly.co) - Rallly is an open-source alternative to Doodle that lets you create polls to vote on dates and times. ([Source Code](https://github.com/lukevella/Rallly)) `AGPL-3.0``Nodejs`
- [RetroShare](https://retroshare.cc) - Secured and decentralized communication system. Offers decentralized chat, forums, messaging, file transfer. ([Source Code](https://github.com/RetroShare/RetroShare)) `GPL-2.0``C++`
- [RetroShare](https://retroshare.cc) - Secured and decentralized communication system. Offers decentralized chat, forums, messaging, file transfer. ([Source Code](https://github.com/RetroShare/RetroShare)) `GPL-2.0``C++`
- [Revolt](https://revolt.chat/) - Revolt is a user-first chat platform built with modern web technologies. ([Source Code](https://github.com/revoltchat/revolt)) `AGPL-3.0``Rust`
- [Revolt](https://revolt.chat/) - Revolt is a user-first chat platform built with modern web technologies. ([Source Code](https://github.com/revoltchat/revolt)) `AGPL-3.0``Rust`
- [Rocket.Chat](https://rocket.chat/) - Teamchat solution similar to Gitter.im or Slack. ([Source Code](https://github.com/RocketChat/Rocket.Chat)) `MIT``Nodejs`
- [Rocket.Chat](https://rocket.chat/) - Teamchat solution similar to Gitter.im or Slack. ([Source Code](https://github.com/RocketChat/Rocket.Chat)) `MIT``Nodejs/Docker/K8S`
- [Screensy](https://github.com/screensy/screensy) - Simple peer-to-peer screen sharing solution for sharing your screen with WebRTC. ([Demo](https://screensy.marijn.it/)) `GPL-3.0``Nodejs`
- [Screensy](https://github.com/screensy/screensy) - Simple peer-to-peer screen sharing solution for sharing your screen with WebRTC. ([Demo](https://screensy.marijn.it/)) `GPL-3.0``Nodejs/Docker`
- [Shhh](https://github.com/smallwat3r/shhh) - Keep secrets out of emails or chat logs, share them using secure links with passphrase and expiration dates. `MIT``Python`
- [Shhh](https://github.com/smallwat3r/shhh) - Keep secrets out of emails or chat logs, share them using secure links with passphrase and expiration dates. `MIT``Python`
- [SimpleX Chat](https://github.com/simplex-chat/simplex-chat) - The most private and secure chat and applications platform - now with double ratchet E2E encryption. `AGPL-3.0``Haskell`
- [SimpleX Chat](https://github.com/simplex-chat/simplex-chat) - The most private and secure chat and applications platform - now with double ratchet E2E encryption. `AGPL-3.0``Haskell`
- [Soketi](https://soketi.app/) - Soketi is a free, open-source Pusher drop-in alternative. ([Source Code](https://github.com/soketi/soketi)) `MIT``Nodejs`
- [Soketi](https://soketi.app/) - Soketi is a free, open-source Pusher drop-in alternative. ([Source Code](https://github.com/soketi/soketi)) `MIT``Nodejs/Docker/K8S`
- [Spectrum 2](https://spectrum.im/) - Spectrum 2 is an open source instant messaging transport. It allows users to chat together even when they are using different IM networks. ([Source Code](https://github.com/SpectrumIM/spectrum2)) `GPL-3.0``C++`
- [Spectrum 2](https://spectrum.im/) - Spectrum 2 is an open source instant messaging transport. It allows users to chat together even when they are using different IM networks. ([Source Code](https://github.com/SpectrumIM/spectrum2)) `GPL-3.0``C++`
- [StoneAge Messenger](https://cweb.gitlab.io/StoneAge.html) - A self-hosted Android messenger, S3-compatible storage is the only backend needed. ([Source Code](https://gitlab.com/cweb-repos/cweb-conversations), [Clients](https://f-droid.org/en/packages/com.cweb.messenger/)) `GPL-3.0``Java`
- [StoneAge Messenger](https://cweb.gitlab.io/StoneAge.html) - A self-hosted Android messenger, S3-compatible storage is the only backend needed. ([Source Code](https://gitlab.com/cweb-repos/cweb-conversations), [Clients](https://f-droid.org/en/packages/com.cweb.messenger/)) `GPL-3.0``Java`
- [Synapse](https://matrix-org.github.io/synapse/latest/) - Server for [Matrix](https://matrix.org/), an open standard for decentralized persistent communication. ([Source Code](https://github.com/matrix-org/synapse)) `Apache-2.0``Python`
- [Synapse](https://matrix-org.github.io/synapse/latest/) - Server for [Matrix](https://matrix.org/), an open standard for decentralized persistent communication. ([Source Code](https://github.com/matrix-org/synapse)) `Apache-2.0``Python`
- [Syndie](https://syndie.de) - Syndie is a libre system for operating distributed forums. `CC0-1.0``Java`
- [Syndie](https://syndie.de) - Syndie is a libre system for operating distributed forums. `CC0-1.0``Java`
- [Tailchat](https://tailchat.msgbyte.com/) - Next generation noIM application in your own workspace, not only another Slack/Discord/rocket.chat. ([Demo](https://nightly.paw.msgbyte.com/), [Source Code](https://github.com/msgbyte/tailchat)) `Apache-2.0``Docker`
- [Tailchat](https://tailchat.msgbyte.com/) - Next generation noIM application in your own workspace, not only another Slack/Discord/rocket.chat. ([Demo](https://nightly.paw.msgbyte.com/), [Source Code](https://github.com/msgbyte/tailchat)) `Apache-2.0``Docker/K8S/Nodejs`
- [TextBelt](https://github.com/typpo/textbelt) `⚠` - Outgoing SMS API that uses carrier-specific gateways to deliver your text messages for free, and without ads. `MIT``Javascript`
- [TextBelt](https://github.com/typpo/textbelt) `⚠` - Outgoing SMS API that uses carrier-specific gateways to deliver your text messages for free, and without ads. `MIT``Javascript`
- [Tiledesk](https://tiledesk.com) - All-in-one customer engagement platform from lead-gen to post-sales, from WhatsApp to your website. With omni-channel live agents and AI-powered chatbots. Self hosted alternative to Intercom, Zendesk, Tawk.to and Tidio. ([Source Code](https://github.com/Tiledesk/tiledesk)) `MIT``Docker/K8S`
- [Tiledesk](https://tiledesk.com) - All-in-one customer engagement platform from lead-gen to post-sales, from WhatsApp to your website. With omni-channel live agents and AI-powered chatbots. Self hosted alternative to Intercom, Zendesk, Tawk.to and Tidio. ([Source Code](https://github.com/Tiledesk/tiledesk)) `MIT``Docker/K8S`
- [Tox](https://tox.chat/) - Distributed, secure messenger with audio and video chat capabilities. ([Source Code](https://github.com/TokTok/c-toxcore)) `GPL-3.0``C`
- [Tox](https://tox.chat/) - Distributed, secure messenger with audio and video chat capabilities. ([Source Code](https://github.com/TokTok/c-toxcore)) `GPL-3.0``C`
- [Typebot](https://typebot.io) - Typebot is a conversational app builder as an alternative to Typeform or Landbot. ([Source Code](https://github.com/baptisteArno/typebot.io)) `AGPL-3.0``Docker`
- [Typebot](https://typebot.io) - Typebot is a conversational app builder as an alternative to Typeform or Landbot. ([Source Code](https://github.com/baptisteArno/typebot.io)) `AGPL-3.0``Docker`
- [WBO](https://github.com/lovasoa/whitebophir) - Web Whiteboard to collaborate in real-time on schemas, drawings, and notes. ([Demo](https://wbo.ophir.dev/)) `AGPL-3.0``Nodejs/Docker`
- [WBO](https://github.com/lovasoa/whitebophir) - Web Whiteboard to collaborate in real-time on schemas, drawings, and notes. ([Demo](https://wbo.ophir.dev/)) `AGPL-3.0``Nodejs/Docker`
- [Yopass](https://github.com/jhaals/yopass) - Secure sharing of secrets, passwords and files. ([Demo](https://yopass.se/)) `Apache-2.0``Go`
- [Yopass](https://github.com/jhaals/yopass) - Secure sharing of secrets, passwords and files. ([Demo](https://yopass.se/)) `Apache-2.0``Go/Docker`
- [Zulip](https://zulip.org) - Zulip is a powerful, open source group chat application. ([Source Code](https://github.com/zulip/zulip)) `Apache-2.0``Python`
- [Zulip](https://zulip.org) - Zulip is a powerful, open source group chat application. ([Source Code](https://github.com/zulip/zulip)) `Apache-2.0``Python`