TeamSpeak

vs

Skype

A VoIP application and platform designed for creating communities and connecting gamers, and people rallying around specific causes. The Discord client is a free to use and can handle text, image, video and audio communication between users in a chat channel. Currently over 250 million users use the software to connect with others across the globe.

Mumble is a free and open-source voice over IP application primarily designed for gamers. The application features a customizable in game overlay, application skins, conversation recording, and advanced voice activity detection. Anyone can download and use Mumble for free, but if you want your own server, you can rent a managed solution from the company behind Mumble, or host your own.

..

Zoom is a commercial video and web conferencing software that can be used for webinars or team collaboration and communication. The software is developed by the Chinese and American company Zoom Video Communications, Inc. Zoom provides a cloud platform that is used and loved by many enterprises and fortune 500 companies, due to the easy-of-use and infrastructure-less nature of the platform.

WeChat connects a billion people with voice calls, video calls, photo sharing, chats and payments. The multi-purpose application is developed by the Chinese company Tencent and is and in China, it is described as "the app for everything". WeChat is primarily developed for the mobile consumer, but is also avalible on desktop and in the browser.

Viber is a cross-platform voice over IP application that allow people to make free and secure calls and messages to anyone, anywhere. With Viber, you can create group chats and make group calls, send stickers and emojis over chats that are 100% synced between devices, including 1-tap transfer of calls. Viber is available for free on Android, iOS, macOS, Linux and Windows.