Thunderbird is a free, open source, cross-platform e-mail, news and instant messaging client. The project strategy is modeled after Mozilla Firefox.
- - Thunderbird is the most popular Windows, Mac & Linux alternative to Sim-IM.
- - Thunderbird is the most popular Open Source & free alternative to Sim-IM.
Pidgin is an easy to use, multi-protocol chat client client used by millions. Connect to AIM, MSN, Yahoo, XMPP, and more chat networks all at once. It has built-in support for NSS, offering client-to-server message encryption for protocols that support it.
Facebook Messenger is a faster way to message. Reach friends right on their phones, get and send messages fast, message everyone at once and more.
- - Facebook Messenger is the most popular Web-based, Android, iPhone, iPad & Android Tablet alternative to Sim-IM.
Facebook Messenger Features
Adium is a free and open source instant messaging application for Mac OS X, written using Mac OS Xs Cocoa API, released under the GNU GPL and developed by the Adium team. Based on the libpurple protocol library, Adium can connect you to any number of messaging accounts on any...
The last update is from March 2021.
Trillian is an instant messaging app that works on phones, tablets, and desktops while keeping your chats neatly synchronized between all of them! We think conversation should be easily shared between all of your devices, not trapped as text messages on your phone.
- - Trillian is the most popular SaaS alternative to Sim-IM.
Franz is a free messaging app / former Emperor of Austria and combines chat & messaging services into one application. Franz currently supports Slack, WhatsApp, WeChat, HipChat and many more. You can download Franz for Mac, Windows & Linux.
Empathy is a messaging program which supports text, voice, video chat, and file transfers over many different protocols. You can tell it about your accounts on all those services and do all your chatting within one application.
Empathy is currently unmaintained. Last version, 3.25, released in August 2017, can be still downloaded from the official website.
Imo is a free, simple,secure and faster international video call & instant messaging app.
Psi is a cross-platform powerful XMPP client designed for experienced users. Psi+ is a development branch of Psi with rolling release development model.
Users who wants to receive new features and bug fixes very quickly may use Psi+ on daily basis. Users who do not care about ne.
ICQ is one of the oldest instant messengers. First developed by the Israeli company Mirabilis, sold to AOL, sold again and currenly owned by the Russian "mail.ru" group (known for one of the largest social networks).
Kopete is an instant messenger supporting AIM, ICQ, Jabber, Gadu-Gadu, Novell GroupWise Messenger, and more. It is designed to be a flexible and extensible multi-protocol system suitable for personal and enterprise use.
Chat everywhere! IM+ is the most widely used mobile IM app! Connect all-in-one to MSN, Yahoo!, Google Talk, AIM, Jabber, ICQ, Facebook, MySpace and Twitter on ALL popular mobile platforms.
The widest selection of unique features that you won't find in any other IM client!.