Jitsi

Jitsi is a voice, video-conferencing and instant messaging application that works across different protocols (such as XMPP, SIP, IRC, AIM, and others). When used with the Off-the-Record (OTR) protocol, it enables users to encrypt their instant messages. Jitsi is a secure and privacy-friendly alternative to other services like Skype, Google Hangouts or Facebook Messenger.

Info

Tool type: Chat and VOIP
Ease of use: Requires some patience and effort to install, configure, maintain and troubleshoot
Open source: Yes
Encryption support: Yes
Benefits: Jitsi supports the OTR protocol for the encryption of instant messages, as well as the ZRTP protocol for the encryption of voice calls. Such encryption ensures that communications are secure in transit and that if they were to get compromised, that would not affect past communications. Jitsi also enables users to independently verify their correspondents' identities.
Independent code audit: "None that we know of"
Cost: Free of charge
Languages: English, French, Spanish, Italian and more languages
Compatibility: Windows, Mac OSX and Linux. Android is in Alpha stage
Developed by: Jitsi Team
Version as of this writing: 2.8
Website: Jitsi.org

Last updated: 7 March 2016