Output Messenger Alternatives

Skype is the most popular free voice-over IP and instant messaging service globally. It allows users to text, video and voice call over the internet. Users can also call landlines and mobiles at competitive rates using Skype credit, premium accounts and subscriptions.

Slack is a unified communication platform built with an optimized workflow to keep modern teams focused and productive. A familiar chat interface facilitates discussions while advanced features are easily exposed based on context.

Mattermost is a secure, open source platform for communication, collaboration, and workflow orchestration across tools and teams.

Rocket.Chat is a Web Chat Server, developed in JavaScript, using the Meteor fullstack framework.

Microsoft Teams is the chat-based workspace in Office 365 that integrates your team's people, content, and tools to be increase engagement and efficacy.

Trillian is an instant messaging app that works on phones, tablets, and desktops while keeping your chats neatly synchronized between all of them! We think conversation should be easily shared between all of your devices, not trapped as text messages on your phone.

Ripcord is a desktop chat client for group-centric services like Slack and Discord. It provides a traditional compact desktop interface designed for power users.

Empathy is a messaging program which supports text, voice, video chat, and file transfers over many different protocols. You can tell it about your accounts on all those services and do all your chatting within one application.

Gitter is a chat and collaboration tool for developers and users. It's a place for developers to talk.

Some companies already use Bitrix24 for project collaboration and customer management. Tasks, chats, contacts and VoIP calls - all in one suite. Free for unlimited users.