Gibberbot is an instant messaging app for Android phones, developed by The Guardian Project. Gibberbot implements off-the-record messaging (OTR). Off-the-record messaging is a way to conduct an instant messaging conversation with the following attributes
- Encryption. An eavesdropper cannot read your messages
- Authentication. You can verify the identity of the person you’re chatting to – or at least of the account they are using.
- Deniability. It is not possible for a third party to prove that a particular user sent or received a particular message.
- Perfect forward secrecy. It is not possible for an attacker to decrypt a previous conversation, even if he/she obtains the encryption keys used to encrypt it.
Gibberbot can also use Orbot to route your chats over the Tor network. This prevents an observer from following the source and destination of your messages (effectively, from knowing you are chatting) and provides a way to circumvent web censorship that may involve chat servers being blocked.
Off-the-record messaging only works when both parties in the conversation are using it. This means both parties need to use Gibberbot, another mobile app, or chat software that supports it. Currently Gibberbot is the only option we know of for mobile phones. Off-the-record plugins are available for several PC chat programs, including Pidgin (Windows and Linux), Adium (Mac), Trillian (Windows) and Miranda (Windows).