Matrix is a set of free, open-source and open network standards dedicated to secure, decentralized, real-time encrypted communications. It is published and maintained by the Matrix.org Foundation, which is a non-profit organization, and dedicated to creating an open, independent and evolving communication platform. In 2019, Matrix was out of beta, and its protocol is fully suitable for production usage.

There are already countless chatting software (such as WhatsApp, Skype, Discord, Facebook Messenger), but almost all of them are non-free software based on central servers, and their security and privacy are not guaranteed (any chat history of you will be sold to various companies). Many of them claim to encrypt communication content, even with end-to-end encryption, but when a platform is proprietary, there is simply no way for others to verify that it is as secure and private as it promises to be. Of course, there are some really safe and reliable ones, but they are frequently blocked by governments of various countries and cannot continue (such as Signal, Telegram).

TeamTalk is a free and open-source multi-user conferencing system for Windows, Mac, Linux and mobile platforms, developed by Bjoern D. Rasmussen from Denmark. It allows user to perform real-time voice and video communication through Internet. For voice encoding, it uses the Opus and Speex audio codecs; for video streaming, it uses the WebM video codec.

In 2009, AppNee discovered and collected CyberLink's YouCam this excellent camera effects embedding software in the CD attached with a Lenovo computer for the first time, and once wanted to share it in no time. But due to its too big file size (for a camera auxiliary application), I've been putting its release date at AppNee off, until today.

Skype is currently the world's most popular free HD instant messaging software (and VoIP) for all kinds of desktop and mobile platforms. Low system resource requirement, high-quality voice communication and high stability have won its hundreds of millions of users around the world. After acquired by Microsoft in 2011, it became an independent department of Microsoft. And in 2013, if finally replaced Microsoft's own instant messaging tool MSN. In 2014, it released an embedded web version.