Uup is described as 'Reclaim your privacy With Uup. Uup is based on asymmetric encryption. Private key is generated based on the device and it doesn't need any email, mobile number or anything else to work' and is a Encrypted Chat app in the social & communications category. There are more than 50 alternatives to Uup for a variety of platforms, including Android, Windows, Linux, Mac and iPhone apps. The best Uup alternative is Signal, which is both free and Open Source. Other great apps like Uup are Telegram, Element, Matrix and Tox.
Technitium Mesh is a secure, anonymous, peer-to-peer (p2p), open source instant messenger designed to provide end-to-end encryption. Primary aim of developing this instant messenger is to provide privacy which is achieved using cryptography and anonymity using Tor network.
India
Germany
EU
TorChat is a peer to peer instant messenger with a completely decentralized design, built on top of Tor's location hidden services, giving you extremely strong anonymity while being very easy to use without the need to install or configure anything.
Conduit is a simple, fast and reliable chat server powered by Matrix. Conduit is an alternative to Synapse and tries to be lightweight and easy to install, but it is still in development.
Tinfoil Chat (TFC) is a FOSS+FHD peer-to-peer messaging system that relies on high assurance hardware architecture to protect users from passive collection, MITM attacks and most importantly, remote key exfiltration.
Kontalk is a secure instant messenger, allowing you to send and receive text, image and voice messages (other file types coming soon) to and from other Kontalk users completely free of charge.
ItalyEU
FireFloo is an instant messaging communicator combining the open XMPP standard (Jabber, GMail Chat etc.) with the echo protocol for multi-encrypted messaging. Use various methods to send chipertext over open standards like libgcrypt and encrypt your private communication.
Utopia P2P Ecosystem. Utopia is a feature-rich platform that is specifically designed to protect privacy of communication, confidentiality, and security of personal data. Utopia is a decentralized network, with no central server involved in data transmission or storage.
Iceland
Antox is an Android client for Tox. It aims to bring the full multimedia support Tox offers to your device, although it's still currently in heavy development.
FortKnoxster is a multidevice easy-to-use private and secure messaging, calling, crypto wallet and cloud storage, using advanced end-to-end encryption and leveraging on blockchain technology.
United Kingdom
KakaoTalk is a phone number based messenger service that allows users anywhere in the world to chat one-to-one or in a group for free. (no SMS service)
South Korea
