Ring (SFLphone) is an open-source SIP-compatible softphone and instant messenger for Linux, Microsoft Windows, OS X and Android. Developed by Savoir-faire Linux
License: Open Source
RetroShare is a decentralized communication platform focused on privacy and file sharing, while Ring offers a simpler interface with end-to-end encryption and calling features. RetroShare is more suited for users needing extensive file sharing and privacy, whereas Ring appeals to those looking for straightforward communication.