Alternatives to Slack for Linux with any license

Discord

All-in-one voice, video and text chat for gamers that’s free, secure, and works on both your desktop and phone.
- Slack is a project productivity and communication enhancement tool with integrating with other collaborative tools like GitHub, document editors, storage, etc. Discord is for recreational chatting. thompsonmj • Aug 2018 • 13 agrees and 6 disagrees
- Good app for your personal use. Wouldn't recommend for an Enterprise setting which is what Slack is more geared towards. TheBeast • Jan 2017 • 12 agrees and 1 disagrees
- Better voice quality, easier to setup and use mrlegendanny • Jan 2018 • 5 agrees and 4 disagrees
- It's cheap and very well implemented. Audio features are perfect. It's not enterprise, obviously, but it IS definitely a reference to follow. rdlu • Jul 2018 • 0 agrees and 1 disagrees
- slack is bassicly discord, & discord has GAMING OPTIONS un like slack Guest • Jul 2018 • 0 agrees and 6 disagrees
- Discord is more gamer oriented than business oriented. alexandrezanni • Jan 2018 • 5 agrees and 5 disagrees
- Great app that even supports video meetings Guest • Apr 2016 • 7 agrees and 2 disagrees
- It's basically Slack with voice support Guest • Feb 2016 • 0 agrees and 1 disagrees
- Discord is pure chat for gamers Guest • Feb 2016 • 1 agrees and 3 disagrees
Freemium $ $ $ Mac Windows Linux Web Android ... iPhone Chrome OS BSD iPad FreeBSD
Voice Call Share your screen Ad-free Chat Bot ... Text chat Video calling Group chat Push to talk Custom roles Direct Messaging Encrypted chat Group Voice Chat Low Latency Multi Channel Public groups chat Reactions Voice channels Bots Camera capturing Channel manager Community based Custom Smileys Dedicated Server Hosting Development API Electron based Free voice/text servers Gaming-focused Gui Group Messaging In-app server browser In-Game Overlay Integrated Chat Integrated File Sharing Interface Overlay Low bandwidth usage Low memory usage Night mode/Dark Theme Permission system Persistent Chat Photo Sharing Positional audio Responsive design Share your screen Share content Single Sign-On Social & Communications Team Collaboration Webcam overlays Youtube Gaming Integration Add a feature

634 Like
Mattermost

Mattermost is an open source, self-hosted Slack alternative. As an alternative to proprietary SaaS messaging, Mattermost brings...
- Same functionality. Same interface. At the same time, there are much fewer restrictions. IN my experience, the free version is great enough for a team of 100 people shelehovchanin • Apr 2019 • 3 agrees and 0 disagrees
- it is similar in features, and has some more, for example XMPP compatibility (-> many more client choice) and ability to self host it! Guest • Jul 2018 • 2 agrees and 0 disagrees
- Mattermost is quite versatile and has been used within several of my past employers. Guest • May 2018 • 2 agrees and 1 disagrees
- Its the same but you keep your server where you want so no one is playing with your data, and you can have an unlimited history depending on what you need for free so really way better ! Guest • May 2017 • 5 agrees and 1 disagrees
- It is very much a Slack clone with added features + it's open source! Guest • May 2017 • 3 agrees and 2 disagrees
- 1. Open source; 2. most of the same functionality; 3. secure and private server possibilities (the data is, therefore, yours until the end of time); 4. extra features when it comes to customization, a big difference actually. Only negative is that Slack look a lot better design wise, so you can't customize it optimally. Guest • May 2017 • 1 agrees and 1 disagrees
Freemium $ $ $ Open Source Mac Windows Linux Android iPhone ... Android Tablet iPad Self-Hosted JavaScript Go (Programming Language) Cloudron
Team Collaboration Group chat Data API Integrated File Sharing ... MarkDown support Multi Channel On-premises software Plugin API File Sending Slack integration Supports XMPP Add a feature

160 Like
Riot.im

Riot (formerly Vector) is an opensource interoperable app running on Web, iOS and Android. It is built around chat rooms, both public and private and provides messaging...
- Federated, decentralized, encrypted, open-source. Guest • Jul 2019 • 2 agrees and 1 disagrees
- because its open source, decentralised, and end-to-end secure. Plus the folks at matrix.org are working to get us out of our communication silos by creating standards for communication interoperability! brinerustle • Mar 2018 • 3 agrees and 0 disagrees
- Federated, free standard and free software Guest • Feb 2018 • 2 agrees and 1 disagrees
- decentralised, federated, end-to-end encrypted communication. User6044478 • Oct 2017 • 6 agrees and 0 disagrees
- Free and opensource with better performance and features for team communication. Guest • Aug 2017 • 3 agrees and 1 disagrees
- It's built atop Matrix, which provides distributed, federated instant messaging, voice and video calling with the ability to bridge into other networks (IRC, etc.) lampholder • Jul 2017 • 3 agrees and 0 disagrees
Free Open Source Mac Windows Linux Web Android ... iPhone Android Tablet iPad Self-Hosted Chrome Safari F-Droid Firefox
Apps with End-to-End Encryption Decentralized Voice Call Custom widgets ... Federated Group chat Matrix.org protocol User Management Video calling Add-ons Clean design Community based Direct Messaging DRM Free Encrypted chat GitHub integration Group collaboration Integrated File Sharing MarkDown support Mobile friendly Privacy-friendly Self-hosted in intranet or private cloud File Sending Server Moderation Server side history Slack integration Team Collaboration Video calling Web Integaration Add a feature

251 Like
Zulip

Zulip is a group chat app. Its most distinctive characteristic is that messages are threaded by topic, helping you have long-running, organized conversations....
- The concept of topics to each message is a super useful feature :) Guest • May 2019 • 1 agrees and 1 disagrees
- Zulip is open source and the methods of communications used is vastly different. It is specially useful in professional environments where different teams might want to participate in different conversations at the same time. Zulip solves this problem by including topics, where in each channel/stream, multiple topics can exist at once, at the same time. Guest • Mar 2019 • 1 agrees and 0 disagrees
- Open Source without limitations when on premises. Much better information categorisation with Streams & Topics. Vibrant community. superbiche • Dec 2018 • 1 agrees and 1 disagrees
- One can easily switch in between conversation between different threads! Extremely helpful for any organisation. shantnukumar • Aug 2018
- Three reasons: 1. Open source. 2. Stream 3. Topics abijith • Dec 2017 • 5 agrees and 0 disagrees
- It's open source and you can self host. It has great threading to group conversations so things are easier to find and more organized . Guest • Jul 2018
- It's open source, and has really good threaded conversations. aviendha1591 • Nov 2017 • 5 agrees and 0 disagrees
- Zulip offers a great unbeatable chatting experience. It shines in many places where Slack tends to slack. Sethu • Dec 2017 • 5 agrees and 0 disagrees
- Zulip is very user friendly and is also open source! linacodes • Jan 2018
- It is open source and has a lot of topics. Guest • Jan 2018
- Open-source, streams, topics, quick responses from devs hrishikeshpatil • Jan 2018
- Great community Easy Access Many organization sirepherox • Jan 2018
- Good community with great support. gamefreakerxD • Dec 2017
Free Open Source Mac Windows Linux Web Android ... iPhone Android Tablet BSD Self-Hosted
Threaded Conversations Group collaboration Chat Bot Community based ... GitHub integration Group chat Integrated File Sharing Live topics MarkDown support Team Collaboration Add a feature

142 Like
Rocket.Chat

Rocket.Chat is a Web Chat Server, developed in JavaScript, using the Meteor fullstack framework.
- Rocket.Chat comes very close to slack regarding it's core features and handling. Guest • Jun 2018 • 1 agrees and 0 disagrees
- open source, locally hosted so you own your data. Guest • Nov 2018 • 0 agrees and 1 disagrees
- Does everything Slack does AND it's open source. However, it's also self-hosted. This means you have to put in the effort to set it up, but you control your own data, which is a huge advantage to your privacy - your chats and files don't sit on someone else's servers, ready for them or hackers to look at. JohnFastman • Dec 2016 • 4 agrees and 1 disagrees
Free Open Source Mac Windows Linux Android iPhone ... Self-Hosted Cloudron
Group chat Live Chat Video Conferencing Ad-free ... Channels Chat Bot Extensible by Plugins/Extensions Integrated File Sharing Location Mapping Share your screen Self-Serve Capability Slack integration Voice messages Add a feature

90 Like
Wire

Wire is the most secure collaboration platform featuring messenger, voice, video, conference calls, file-sharing, and external collaboration –all protected by the most...

Free Open Source Mac Windows Linux Web Android ... iPhone Android Tablet iPad Software as a Service (SaaS)
Apps with End-to-End Encryption Security focused Encrypted chat Video calling ... Open Source apps Voice Call Encrypted calls Encryption Group chat Share your screen Anonymity Integrated File Sharing Multiple Account support Photo Sharing Privacy focused Privacy Protected Private Chat Secure File Sharing File Sending Video calling Voice messages WebRTC Add a feature

228 Like
Matrix.org

Matrix defines a set of open APIs for decentralised communication, suitable for securely publishing, persisting and subscribing to data over a global open federation of...
- Matrix is a protocol, not a client. somegirlfromit • Sep 2019 • 1 agrees and 0 disagrees
- Respects your Freedom. Increasingly popular Guest • Nov 2017
- Open source, fecentralized, federation, chat-voice-video function. User6044478 • Oct 2017
- Free open source instant messaging service with federation. Guest • Aug 2017 • 0 agrees and 1 disagrees
- It can be easily bridged to many other chat systems, including Slack, which makes transitioning *much* easier. It's also open source and decentralized (self-hostable + communication with other servers). Guest • Jul 2017
- Capable of everything Slack can do, but can be self-hosted - keeping a team's data in-house. nrg200 • Jul 2017
Free Open Source Mac Windows Linux Web Android ... iPhone Android Tablet iPad Self-Hosted WebRTC Python JavaScript Go (Programming Language) Java Perl
Apps with End-to-End Encryption Chat Decentralized Chat Bot ... Distributed Encrypted chat GNU/linux-libre Group chat Java Random video chat Real time collaboration Server side history Team Collaboration Voice Call WebRTC Add a feature

129 Like
Jitsi

Jitsi (previously SIP Communicator) is an audio/video and chat communicator with full end-to-end encryption that supports protocols such as SIP, XMPP/Jabber, ICQ/AIM...

Free Open Source Mac Windows Linux Web Android ... iPhone BSD iPad
SIP Video Conferencing Chat Apps with End-to-End Encryption ... Group chat iPhone/iPod sync Support for Multiple protocols Multiple Account support OTR Plugins SIP Video calling WebRTC Add a feature

300 Like
Keybase

Keybase is a new and free security app for mobile phones and computers. For the geeks among us: it's open source and powered by public-key cryptography. Keybase...
- it's encripted, developed fast, and has crypto airdrops BandiLaszlo • Sep 2019
- it's not suitable for chatting in a organization, with channels, file sharing etc Guest • Jul 2018 • 4 agrees and 5 disagrees
Free Open Source Mac Windows Linux Web Android ... iPhone Ruby JavaScript Go (Programming Language) Java
Encrypted chat Git integration Ad-free Connecting Mastondon Identities ... Drive Encryption Encryption Apps with End-to-End Encryption Facebook integration GitHub integration Java PGP Encryption Private repositories Public key encryption Security focused Self destructing messages Team Collaboration Twitter integration Two-Step verification Add a feature

58 Like
HipChat

HipChat is an instant messaging service designed for companies and teams. It has persistent chat rooms, one-to-one chat, searchable chat history, file sharing via drag...
- Discontinued https://alternativeto.net/software/slack/ is acquiring Hipchat and https://alternativeto.net/software/stride-by-atlassian/ from Atlassian. the services will be discontinued after February 15th, 2019. https://www.atlassian.com/partnerships/slack
- Simple, very fast desktop client. Good web client. Guest • Feb 2018
Freemium Mac Windows Linux Web Android ... iPhone Android Tablet iPad Self-Hosted Apple Watch
Team Collaboration Chat Integrated File Sharing Share your screen Add a feature

73 Like
Gitter

Gitter is a chat and collaboration tool for developers and users. It's a place for developers to talk. KEY FEATURES - Unlimited public chat rooms for free -...

Free Open Source Mac Windows Linux Web Android ... iPhone
Chat Real time collaboration Add a feature

29 Like
Twist

A communication app for teams who want to create a calmer, more organized, more productive workplace.
- A less distracting communication app which manages notifications better. samrubens • Apr 2019
- Topics (the killer feature that's made Slack frustrating), excellent, clean design, very easy to onboard, integrations, channels, messaging, etc. Guest • Jun 2018
Freemium $ $ $ Mac Windows Linux Android iPhone ... Android Tablet iPad
beta Chat Bot Indexed search Threaded Conversations Add a feature

15 Like
eXo Platform

eXo Platform is a Digital Workplace solution for enterprises. It helps people work together in a collaborative workplace.

Freemium $ $ $ Open Source Mac Windows Linux Web Android ... iPhone iPad Self-Hosted Software as a Service (SaaS)
App integration Chat File sharing Group collaboration ... Real time collaboration Shared calendars Software as a Service Task Management Team Collaboration Team messaging Team work Add a feature

61 Like
Dialog Messenger

Dialog Messenger is a customized self-hosted platform usable across multi operation systems simultaneously. dialog provides SDK tools for client interface as well as for...

Free Personal Mac Windows Linux Web Android ... iPhone Self-Hosted Software as a Service (SaaS)
Encrypted chat Reactions Real time collaboration Security & Privacy ... Team work Text chat Add a feature

25 Like
ZeroChat

An IRC-like internet chatroom hosted on ZeroNet, a distributed network. 0rc is a fully distributed website, and messages are shared through peers using the ZeroNet...

Free Open Source Mac Windows Linux Web Self-Hosted ... Python JavaScript ZeroNet
Decentralized Distributed Add a feature

10 Like