Otr.to is an “Off-the-Record” (OTR) Messaging, a cryptographic protocol for encrypting instant messaging applications. The app could prove to be a great tool for a variety of people, including journalists, businesses and whistle blowers who want to keep their communications instant, private and secure. It is based upon open source JavaScript libraries i.e. Crypto-js, PeerJS and Off-The-Record Messaging Protocol. The service is free and anonymous, which means it doesn’t reveal anybody’s identity to public.
Source: https://thehackernews.com/2015/03/otr-secure-off-record-p2p-chat.html