Rakuten Viber is described as 'Secure messaging, free calls, group chats up to 250, emoji reactions, disappearing messages, low-cost international calls, rich media and community channels' and is a very popular instant messenger in the social & communications category. There are more than 100 alternatives to Rakuten Viber for a variety of platforms, including Android, iPhone, Web-based, iPad and Android Tablet apps. The best Rakuten Viber alternative is Signal, which is both free and Open Source. Other great apps like Rakuten Viber are Telegram, Element, Tox and WhatsApp.
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.
Fully open source instant messaging server and clients. No proprietary components or non-free dependencies. Backend in pure Go (GPL 3.0), with a command-line administration tool in python + gRPC. Clients for Android, iPhone, and Web - ReactJS (all licensed under Apache 2.0).
Vector encompasses the ideals of freedom through free and open-source technology, using a "Privacy by Principle" approach. This means that privacy is not a feature or add-on, but the core foundation that Vector is built upon, which is granted and accessible to everyone.
This project won the first prize 🥇 at Telegram Lightweight Client Contest and now is an official Telegram client available to anyone at web.telegram.org/a.
VeilidChat is a 1-to-1, person-to-person text only chat application which serves as a technology demonstration for the Veilid application development framework. All communication is end to end encrypted, authenticated, private routed, and peer-to-peer. It's currently in early beta.
Kik is way more than just messaging. It’s the easiest way to connect with your friends, stay in the loop, and explore – all through chat. No phone numbers, just pick a username.
monocles chat is a fork of blabber.im and Conversations with some changes, to improve usability.
Offers free global video and voice calling, group chat with up to 50 participants, in-app messaging that bypasses SMS plans, music clip sharing via Spotify, photo editing, gaming and gifts, animated messages, mini-games during calls, and centralized media gallery.
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)
Russia
United States
Germany
EU
Cyprus
Vietnam
South Korea