Hangouts Alternatives for Mac OS X

Skype is an instant messaging and VOIP (Voice Over Internet Protocol) client to communicate with people in a distant place.

Pidgin is a free and open-source chat client which supports AIM, Google Talk, ICQ, XMPP protocols.

Telegram is a free cloud-based instant messaging platform.

WhatsApp Messenger is an instant messaging platform owned by Facebook.

Slack is a cloud-based team collaboration tool.

Tox is a peer-to-peer instant-messaging and video-calling protocol that offers end-to-end encryption.

Trillian is a proprietary multiprotocol instant messaging application.

Viber Free Messenger and Phone Calls.

Discord is a freeware proprietary VoIP application designed for gaming communities.

Signal is the most scalable encryption tool.

Jitsi (formerly SIP Communicator) is a free and open source multiplatform voice (VoIP), videoconferencing and instant messaging application.

LINE is a new communication app which allows you to make free voice calls and send free messages whenever and wherever you are.

Wire is a cross-platform, encrypted instant messaging client created by Wire Swiss. It is available for iOS, Android, Linux, Windows, macOS and Web browser clients.

Franz is a free messaging app /former emperor of Austria, that combines chat & messaging services into one application.

Ring (SFLphone) is an open-source SIP-compatible softphone and instant messenger for Linux, Microsoft Windows, OS X and Android.

FaceTime is a proprietary videotelephony product developed by Apple Inc. FaceTime Audio is an audio-only version.

WeChat is a social media with instant messaging, commerce and payment services application.

Matrix is an open protocol for real-time communication. It is designed to allow users with accounts at one communications service provider to communicate with users of a different service provider via online chat, Voice over IP, and Videotelephony.

KakaoTalk (Korean: 카카오톡), or sometimes KaTalk, is a free mobile instant messaging application for smartphones with free text and free call features.

Rambox is a free and Open Source messaging and emailing app that combines common web applications into one.

Tencent QQ (QQ) is an instant messaging software service.

Zulip is a chat and collaborative software.

QuteCom (WengoPhone) is a free-software SIP-compliant VoIP client.

Dialog Messenger is a handy and feature-rich enterprise multi-device messenger available for server or cloud.

Tkabber is a GPL instant messaging client for the XMPP protocol which uses the Tk toolkit for the GUI.

MySMS is a family of applications helps you text anywhere and enhances your messaging experience on your smartphone, tablet and computer.

YakYak is a desktop chat client for Google Hangouts.

Toky is an automation platform.