Telegram
Free
Telegram is a free cloud-based instant messaging platform.
Viber
Freemium
Viber Free Messenger and Phone Calls.
Jitsi
Open Source
Jitsi (formerly SIP Communicator) is a free and open source multiplatform voice (VoIP), videoconferencing and instant messaging application.
Linphone
Open Source
Linphone is a free voice over IP (VoIP) service and SIP client.
Wire
Free
Wire is a cross-platform, encrypted instant messaging client created by Wire Swiss. It is available for iOS, Android, Linux, Windows, macOS and Web browser cl…
Gajim
Open Source
Gajim is an instant messaging client for the XMPP protocol which uses the GTK+ toolkit.
Zulip
Open Source
Zulip is a chat and collaborative software.
Tkabber
Open Source
Tkabber is a GPL instant messaging client for the XMPP protocol which uses the Tk toolkit for the GUI.
Toky
Freemium
Toky is an automation platform.
Trillian
Freemium
Trillian is a proprietary multiprotocol instant messaging application.
Signal
Open Source
Signal is the most scalable encryption tool.
Empathy
Open Source
Empathy is an instant messaging (IM) and voice over IP (VoIP) client which supports text, voice, video, file transfers, and inter-application communication ov…
Psi
Open Source
Psi is a free instant messaging application designed for the XMPP network (including Google Talk). Fast and lightweight, Psi is fully open-source and compatib…
ICQ
Free
ICQ is an open source instant messaging software.
Zoiper
Freemium
Zoiper is an easy to use sip video softphone, with excellent voice quality and easy to setup.
QuteCom
Open Source
QuteCom (WengoPhone) is a free-software SIP-compliant VoIP client.
YakYak
Open Source
YakYak is a desktop chat client for Google Hangouts.
