Alternatives to Vacuum-IM for all platforms with any license

Pidgin

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...

Free Open Source Mac Windows Linux BSD PortableApps.com ... Xfce
Multiple protocols Multiple protocols support Extensible by Plugins/Extensions Supports XMPP ... Multiple languages Multiple Account support Multiple chat protocols Portable Video calling Voice Call Add a feature

1439 Like
Jitsi

Jitsi (previously SIP Communicator) is an audio/video and chat communicator with full end-to-end encryption that supports protocols such as SIP, XMPP/Jabber, ICQ/AIM...

Free Open Source Mac OS X Windows Linux Web Android ... BSD
End-to-end encryption Group chat iPhone/iPod sync Multiple protocols ... Multiple Account support OTR Video calling WebRTC Add a feature

275 Like
Empathy

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...

Free Open Source Linux BSD
Built-in File transfer Multiple protocols Video calling Add a feature

154 Like
- Discontinued Empathy is currently unmaintained. Last version, 3.25, released in August 2017, can be still downloaded from the official website.
Gajim

The goal of Gajim is to provide a full featured and easy to use Jabber client. Gajim works nicely with GNOME, but does not require it to run. It is released under the...

Free Open Source Mac OS X Windows Linux BSD Xfce
Encrypted chat Group chat Multiple languages OTR ... Supports XMPP Tabbed interface Video calling Add a feature

51 Like
YakYak

What does it do: * Send/receive chat messages * Create/change conversations (rename, add people) * Leave/delete conversation * Notifications * ...

Free Open Source Mac Windows Linux Hangouts
Portable Add a feature

17 Like
MetroIRC

An IRC client for the Windows desktop which follows the Metro design guidelines.

Free Open Source Windows
No features added Add a feature

7 Like
Jabiru

Jabber client for Android.

Free Android
No features added Add a feature

5 Like
- Discontinued The app has been discontinued. Last version, 2.2.2.1, released in May 2013, can be still downloaded from Google Play Store.
Caya

Caya is a multiprotocol Instant Messaging client for Haiku. Right now it support: - Google Talk - Jabber - Facebook - MSN Messenger - AOL Instant...

Free Open Source Haiku
No features added Add a feature

2 Like
Centericq

Centericq is a text mode menu- and window-driven IM interface that supports the ICQ2000, Yahoo!, AIM, IRC, MSN, Gadu-Gadu and Jabber protocols.

Free Open Source Mac OS X Windows Linux BSD
Built-in RSS reader Add a feature

1 Like
- Discontinued The program is no longer updated. Last version, 4.21.0, released in September 2005, can be still downloaded from the official website.