Tango Alternatives for Mac OS X

Skype is a versatile communication platform offering free voice and video calls to other Skype users, as well as affordable calls to landlines and mobile phones worldwide. It provides instant messaging, file sharing, and screen sharing features, making it a comprehensive tool for personal and professional connectivity across various devices.

WhatsApp Messenger is a widely used free messaging and calling app, available globally. It enables communication through text, voice messages, and video calls, facilitating connections between individuals and groups across various devices and platforms.

Trillian is a versatile, multi-protocol instant messaging client that unifies various communication platforms like IRC, XMPP, and more into a single, user-friendly interface. It's designed for both personal and team collaboration, offering features like encrypted chats, group collaboration tools, and extensive customization options.

Viber is a comprehensive messaging and VoIP application enabling free and secure calls and messages to users worldwide. It offers robust features for both individual and group communication across various devices.

Signal is a secure, open-source messaging application that uses end-to-end encryption to protect user communications. It offers text messaging, voice and video calls, group chats, and file sharing, all with a strong focus on privacy and security. Available on multiple platforms, Signal is a leading choice for individuals prioritizing confidential conversations.

Jitsi is a free and open-source suite of secure, flexible communication tools. It offers multi-platform support for voice (VoIP), video conferencing, and instant messaging, emphasizing privacy and ease of use with no account required to start a meeting.

LINE is a versatile communication platform offering free voice and video calls, messaging, and a wide array of interactive features to connect with friends and family globally. It goes beyond basic chat with unique stickers, timeline posts, and integration with various services, providing a comprehensive social and communication experience in one app.

Wire is a secure, cross-platform messaging and collaboration client offering end-to-end encryption by default for all communication types including messaging, voice and video calls, and file sharing across desktop and mobile devices.

FaceTime is Apple's integrated video and audio calling service, providing a seamless communication experience across Apple devices. It allows users to connect with friends and family through high-quality video and audio calls, including group conversations.

Ventrilo, commonly known as Vent, was a popular VoIP software designed primarily for group voice communication, widely used by online gamers and communities before its discontinuation. It offered clear voice quality, low latency, and integrated text chat functionalities.

Blink is a robust, real-time communications client leveraging the SIP protocol for secure and private instant messaging, voice, and video calls. It emphasizes features like end-to-end encryption, file sharing, and screen sharing across various platforms.

Coccinella is a free and open-source, cross-platform XMPP/Jabber client. It offers secure instant messaging, group chat, voice chat, and a unique interactive whiteboard feature. Designed with privacy and security in mind, Coccinella provides encrypted communications and supports various communication protocols for a flexible messaging experience on Windows, macOS, and Linux.

Zulip is a powerful open-source group chat application designed for team collaboration. It uniquely structures conversations around topics, enabling users to easily catch up on important discussions and manage information overload. Zulip facilitates secure communication with integrated file sharing and various integrations.

QuteCom, formerly WengoPhone, was a free and open-source VoIP client supporting the SIP protocol. It enabled users to make voice and video calls, send instant messages, and connect with contacts across various networks, including Google Talk.

Dialog Messenger is a robust, feature-rich enterprise messaging solution designed for businesses prioritizing security, privacy, and control. Available for both private server deployment and cloud hosting, it facilitates secure text, voice, and video communication across multiple devices, enabling seamless collaboration and real-time interaction within organizations.

Tkabber is a free and open-source instant messaging client specifically designed for the XMPP protocol. Built with the Tk toolkit, it offers a lightweight yet extensible platform for text-based chat, group conversations, and various interactive functionalities supported by XMPP.

Toky is a comprehensive cloud-based phone system designed for businesses, offering voice calls, SMS, call recording, and integrations with various CRM and business tools. It provides teams with a flexible and powerful communication platform for customer support and internal collaboration.

YakYak is an unofficial desktop client for Google Hangouts, providing a dedicated application experience outside of a web browser with features focused on convenience and improved usability.