RetroShare is an open-source, cross-platform and free software released under the GNU General Public License, it is a decentralized, private and secure commmunication and sharing platform. RetroShare provides filesharing, chat, messages, forums and channels. You can securely communicate with your friends, it lets you to securely chat and share files with your circles, using a web-of-trust to authenticate peers and OpenSSL to encrypt all communication. RetroShare provides filesharing, chat, messages, forums and channels. Retroshare claims on their homepage that "Nobody can spy on you."

Send text and images. Discuss with various people in chat rooms. Express your emotions with the rich smiley set. Use distant chat to securely chat with friends-of-friends. Send encrypted mails/messages to other members of the network. Retroshare can store encrypted messages on friends nodes to deliver messages while you're offline. Share files with your friends or with the whole network. Use the search to find files. Retroshare uses swarming similar to BitTorrent, to accelerate the download. This makes it possible to share big files with 1GB or more. Your privacy is protected with anonymous tunnels. Only your direct friends might learn which files you download. You can read and write forum posts offline. This is perfect while you're on the go. When you have an Internet connection, Retroshare will automatically sync forums with your friends. Decentralized forums are censorship resistant by design.
There is also command-line client, it can be contacted and talked-to using SSL. Clients exist for portable devices running e.g. Android. RetroShare FeedReader plugin provides a plugin for RetroShare, a secured Friend-to-Friend communication plateform. The plugin adds a RSS feed reader tab to Retroshare.

To install Retroshare in 15.04 Vivid/14.04 Trusty/12.04 Precise/Linux Mint 17.x/17/13 open Terminal (Press Ctrl+Alt+T) and copy the following commands in the Terminal:

Download Retroshare for other distributions.
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