Discover top business communication platforms. Compare messaging, calling, and collaboration tools by pricing and reviews.
58 tools
Tools in Communication
RingCentral — RingCentral is a publicly traded, Belmont, California-based provider of AI-powered cloud business communications, offering phone, messaging, video meetings, and contact center software under its RingEX (formerly RingCentral MVP) platform.
Dialpad — Dialpad is an AI-powered business communications platform offering cloud VoIP calling, video meetings, messaging, and an AI-driven contact center built on Google Cloud.
Aircall — Aircall is a cloud-based business phone system with AI voice agents, call coaching, and CRM integrations for sales and support teams.
OpenPhone — OpenPhone is a modern, VoIP-based business phone system for startups and small teams, offering shared phone numbers, calling, texting, and AI-powered call features; the company rebranded to Quo in late 2025.
Zoom Phone — Cloud-based business phone system (VoIP) from Zoom offering metered or unlimited calling plans, auto-attendants, call queues, and AI call summaries.
8x8 — 8x8 is a cloud communications platform providing business phone (UCaaS), contact center (CCaaS), video meetings, and messaging APIs (CPaaS) for companies of all sizes.
Vonage — Vonage is a cloud communications provider offering business VoIP phone systems, contact center software, and programmable communications APIs for voice, SMS, video, and messaging.
Nextiva — Nextiva is a cloud-based unified communications and customer experience platform offering VoIP business phone, video, SMS, and contact center tools for small businesses through enterprises.
Flock — Flock is a team messaging and collaboration app offering channel-based chat, video calls, shared to-dos and third-party app integrations, marketed as an affordable Slack alternative for businesses.
Chanty — Chanty is a team chat and collaboration app combining messaging, voice/video calls, and built-in task management for small and mid-sized teams.
Superhuman — Superhuman is a premium, AI-powered email client for Gmail and Outlook that focuses on speed, keyboard shortcuts, and inbox-zero workflows for professionals and sales teams.
Spark Mail — Spark Mail is an AI-powered email client from Readdle that offers a Smart Inbox, team collaboration, and AI writing and meeting-notes features across desktop and mobile.
Missive — Missive is a shared team inbox and internal chat platform that lets teams collaborate on email, SMS, and social messages from a single app.
Spike — Spike is an AI-powered email and productivity app that turns cluttered inboxes into a chat-like conversational interface, combining email, team messaging, docs, and video calls in one place.
Twist — Twist is an asynchronous, thread-based team communication app made by Doist, the creator of Todoist, built as a deliberate alternative to real-time chat.
Threads — Threads is Meta's free text-based social networking app built by the Instagram team, launched in July 2023 to let users share short posts and join public conversations.
AnonAddy — AnonAddy (rebranded as addy.io) is an open-source email alias service that lets you create unlimited forwarding addresses to protect your real inbox from spam and leaks.
b1gMail — b1gMail is a self-hosted, open-source PHP webmail and groupware platform that lets organizations run their own branded email service with calendar, contacts, and cloud storage.
DebOps — Free, open-source collection of Ansible roles and playbooks for automating the setup of secure, production-ready Debian and Ubuntu infrastructure.
docker-mailserver — docker-mailserver is a free, open-source, self-hosted mail server that bundles Postfix, Dovecot, spam and virus filtering, and DKIM/DMARC into a single Docker container.
Dovel — Dovel is a free, open-source, lightweight SMTP server written in Go that lets developers self-host email sending and receiving for one or more domains with minimal configuration.
Inboxen — Open-source, self-hostable project for generating disposable email inbox aliases; its original hosted instance has shut down.
iRedMail — Open-source installer that deploys a complete, self-hosted mail server with webmail, groupware and anti-spam in minutes.
Mox — Mox is a modern, all-in-one open-source mail server written in Go that bundles SMTP, IMAP4, webmail, and built-in spam and authentication protections into a single low-maintenance binary.
SimpleLogin — SimpleLogin is an open-source email alias service that lets users shield their real email address behind unlimited disposable aliases, now owned by Proton AG.
wildduck — wildduck is an open-source, scalable IMAP and POP3 email server built on Node.js and MongoDB, designed for API-driven mail hosting and horizontal scaling.
Cyrus IMAP — Cyrus IMAP is a free, open-source, scalable email, calendar and contacts server used by ISPs, universities and enterprises to run their own mail infrastructure.
DavMail — Free open-source gateway that lets Thunderbird, Apple Mail, and other clients speak POP, IMAP, SMTP, CalDAV, CardDAV, and LDAP to Microsoft Exchange or Office 365.
Dovecot — Dovecot is a widely deployed, security-focused open-source IMAP and POP3 email server for Unix-like systems, available as a free Community Edition or a commercially supported Pro Edition.
chasquid — chasquid is a free, open-source SMTP email server written in Go, built for simplicity, secure defaults, and easy self-hosting on Linux.
Courier MTA — Courier MTA is an open-source, integrated mail and groupware server providing ESMTP, IMAP, POP3, webmail, and mailing list services under the GPL.
EmailRelay — E-MailRelay is a free, open-source, lightweight SMTP proxy and store-and-forward mail transfer agent written in C++ for Linux and Windows, often used as a local spam-filtering relay.
Exim — Exim is a free, open-source mail transfer agent (MTA) for Unix-like systems, originally built at the University of Cambridge in 1995 and now best known as the default mail server behind cPanel and Debian.
Haraka — Haraka is a free, open source, high-performance SMTP mail server built in Node.js with a fully extensible JavaScript plugin architecture.
OpenSMTPD — OpenSMTPD is a free, open-source SMTP mail server daemon developed as part of the OpenBSD project, focused on security, simplicity, and easy configuration.
Postfix — Postfix is a free, open-source mail transfer agent (MTA) originally written by Wietse Venema at IBM Research as a secure, fast alternative to Sendmail, and today one of the most widely deployed SMTP servers on the internet.
Sendmail — Sendmail is one of the oldest mail transfer agents (MTA) on the internet, originally created at UC Berkeley in the early 1980s, now maintained as an open-source project and Sentrion-based commercial offering under Proofpoint.
Cypht — Cypht is a free, open-source, lightweight webmail client that aggregates multiple email accounts, RSS feeds and calendars into one unified inbox.
Roundcube — Roundcube is a free, open-source AJAX-based webmail client written in PHP that gives IMAP email a desktop-like browser interface.
SnappyMail — Free, open-source webmail client that connects to any IMAP and SMTP mail server through a fast, lightweight, mobile-friendly browser interface.
SquirrelMail — SquirrelMail is a free, open-source webmail client written in PHP that provides IMAP-based email access through a browser, designed to run on low-resource servers with minimal client requirements.
Asterisk — Asterisk is a free, open-source framework for building PBX systems, VoIP gateways, and telephony applications, created in 1999 and maintained by Sangoma.
Flexisip — Flexisip is an open source, modular SIP server suite built by Belledonne Communications for powering VoIP call routing, presence, push notifications, messaging and conferencing infrastructure.
Freepbx — FreePBX is a free, open-source, web-based GUI for managing Asterisk-based phone systems, maintained and sponsored by Sangoma Technologies, powering over a million business phone system installations worldwide.
FreeSWITCH — FreeSWITCH is a free, open-source, software-defined telephony platform supporting SIP, WebRTC, video, and voice communications, created in 2006 and now stewarded by SignalWire, the company its original founders launched in 2017.
FusionPBX — FusionPBX is a free, open-source, multi-tenant PBX and voice-switch web GUI for FreeSWITCH, used to run carrier-grade phone systems, call centers, and white-label VoIP hosting platforms.
Kamailio — Open-source SIP server for building large-scale VoIP, WebRTC and real-time communication platforms.
openSIPS — openSIPS is a free, open-source SIP server used by carriers and telecoms for VoIP infrastructure, maintained by OpenSIPS Solutions in Bucharest, Romania.
Routr — Routr is a free, open-source SIP proxy, registrar, and location server built by Fonoster for deploying VoIP and telephony infrastructure on Docker and Kubernetes.
SIP3 — SIP3 is an open-source, real-time monitoring and troubleshooting platform for VoIP and RTC network traffic, built for support teams handling large call volumes.
SIPCAPTURE Homer — HOMER is a 100% open-source SIP, VoIP, and RTC packet capture and monitoring platform from the SIPCAPTURE project, offering call-flow analysis and drill-down troubleshooting for telecom operators.
Wazo — Open source unified communications platform for building programmable voice, video, messaging, and call center infrastructure.
Yeti-Switch — Open-source SIP session border controller, Class 4 softswitch, and real-time VoIP billing system for telecom carriers and wholesale voice providers.
BetterDiscord — BetterDiscord is a free, open-source client modification for the Discord desktop app that adds custom themes, plugins, and interface tweaks not offered by the official client.
Chatty — Chatty is a free, open-source desktop chat client for Twitch, written in Java, offering an IRC-style interface with Twitch-specific features. It supports joining multiple channels in tabs or separate windows, streamer tools like updating stream title and game from the client, emote autocomplete, and multi-language support, and runs on Windows, macOS, and Linux wherever Java is supported.
connectycube.com — ConnectyCube is a backend-as-a-service platform that provides ready-made SDKs and APIs for in-app chat, peer-to-peer and group video calling, and push notifications. Founded in 2018 and headquartered in Berlin, Germany, it supports iOS, Android, React Native, Flutter, Cordova, NativeScript, and Web, and offers tiered pricing from a free plan up to an Enterprise plan with HIPAA compliance.
Franz — Desktop app that combines 75+ messaging and email services like Slack, WhatsApp, and Gmail into one workspace, built by an independent Vienna-based team since 2016.
getstream.io — GetStream (Stream.io, Inc.) provides API and SDK infrastructure that lets developers add real-time chat, activity feeds, and video/audio calling to their applications without building the backend themselves.