Communication & Collaboration

Self-hosted team chat platform with channels, DMs, voice/video, rich integrations, and omnichannel customer support features.

Alternative to:

Slack+9

Open-source scheduling platform for booking meetings with availability, team routing, integrations, and embeddable booking pages.

Alternative to:

Calendly+9

Self-hostable team chat with channels, threads, calls, integrations, and enterprise-grade security controls for organizations that need full data control.

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Slack+4

Open-source, self-hosted content collaboration: file sync & share, groupware, chat, and optional office collaboration with strong admin and compliance controls.

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Dropbox+3

Self-hostable video conferencing with browser-based meetings, screen sharing, chat, moderation tools, and optional end-to-end encryption.

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Zoom+9

Self-hostable team chat with topic-based threading, powerful search, and integrations for engineering and communities.

Alternative to:

Slack+4

Monica is a personal CRM that helps you manage contacts, log interactions, set reminders, and keep structured notes to maintain better personal and professional relationships.

Alternative to:

Notion+3

Etherpad is a real-time collaborative editor for notes and documents, featuring live multi-user editing, version history, and an extensible plugin system.

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Google Workspace+3

Self-hosted Overleaf Community Edition for collaborative LaTeX editing, real-time PDF preview, version history, and project sharing for teams and classrooms.

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Overleaf (Hosted)+3

Self-hosted shared virtual browser (Firefox/Chromium) with synchronized viewing, multi-user control, chat, and WebRTC streaming for watch parties and remote collaboration.

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Parsec+5

Open-source SMTP delivery platform with web UI, HTTP API, and message tracking for sending transactional email from your own infrastructure.

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Twilio SendGrid+5

Turn a fresh Ubuntu server into a complete mail server with webmail, DNS, spam filtering, automatic TLS, and an easy-to-use admin control panel.

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Google Workspace+7

Gotify is a self-hosted push notification server with a web UI, Android client, and REST API for sending messages from scripts, services, and monitoring tools.

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Pushover+7

All-in-one, Docker-based email server stack with SMTP/IMAP, anti-spam, web UI administration, DKIM, and automated TLS via ACME.

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Gmail+3

Stalwart is an all-in-one mail server (SMTP/IMAP/JMAP) with built-in anti-spam/DMARC, web admin UI, and flexible routing for running your own email infrastructure.

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Microsoft Exchange Online+9

Self-hostable, collaborative spreadsheet-database hybrid with relational tables, formulas, forms, and granular access control—an Airtable alternative.

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Airtable+9

Privacy-first messenger using SimpleX relays and end-to-end encryption, designed to avoid user identifiers, phone numbers, and centralized identity.

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Signal+5

Open-source virtual classroom for web conferencing with whiteboard, screen sharing, breakout rooms, recordings, and LMS integrations.

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Zoom+7

Self-hosted file sync and sharing platform with web/mobile/desktop clients, WebDAV access, sharing controls, versioning, and enterprise-grade security and auditing.

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Dropbox+7

Open-source VoIP voice chat with low latency, positional audio, access control, and a self-hostable server (Murmur) for teams and communities.

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Discord+9

Privacy-focused collaborative office suite with end-to-end encryption for docs, spreadsheets, forms, and file storage.

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Google Workspace+9

Mailu is an all-in-one email server stack (SMTP/IMAP/webmail) packaged for Docker, with anti-spam/AV, DKIM/DMARC support, and a web admin interface for domains and mailboxes.

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Gmail+6

Self-hosted webmail client for IMAP accounts with address book, message search, identities, and an extensible plugin/skin system.

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Gmail+4

Self-hostable email alias manager that generates aliases, forwards mail, and shields your real address with reply support, custom domains, and anti-tracking options.

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Fastmail Masked Email+3

A self-hosted, browser-based IRC client with persistent connections, multi-user access, theming, and extensibility via plugins.

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Kiwi IRC+2

All-in-one SMTP/IMAP mail server with web admin, spam filtering, DKIM/DMARC, and automatic TLS via ACME—designed for simpler, safer email hosting.

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Google Workspace+4

Self-hosted scheduling polls for finding the best time to meet, with shareable links, time zone support, reminders, and optional participant voting.

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Doodle+4

A full-featured EHR/EMR and medical practice management system with scheduling, e-prescribing integrations, billing/claims support, patient portal, and reporting.

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MyChart+9

Create unlimited email aliases and forward mail to your inbox to reduce spam, protect identity, and control who can reach you.

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Apple Hide My Email (iCloud+)+5

A fast, lightweight CalDAV/CardDAV server for syncing calendars, contacts, and tasks with standard clients, featuring filesystem storage and flexible authentication.

Alternative to:

Google Workspace+4