Kadu

Name: Kadu
Availability: Discontinued
Author: KaduTeam

Kadu was a Polish open source instant messaging client that connected to the Gadu-Gadu network - Poland's dominant chat platform before Facebook and WhatsApp. It offered a cleaner, ad-free alternative to the official Gadu-Gadu client, with support for additional protocols like XMPP (Jabber).

What it did

Kadu connected to the Gadu-Gadu network using the open source implementation of the GG protocol, displaying your contact list and letting you chat in real time. Unlike the official GG client, Kadu was ad-free and lighter on system resources. It supported file transfers, message history, and customizable chat windows.

XMPP protocol support allowed connecting to Jabber servers alongside Gadu-Gadu, letting you use one client for multiple messaging networks. The interface was built on Qt and available on both Windows and Linux.

Advantages

Ad-free alternative to official Gadu-Gadu client
Open source and community maintained
Multi-protocol support (GG + XMPP)
Lightweight compared to official client

Drawbacks

Gadu-Gadu network has very few active users today
Development slowed significantly
Modern messaging has moved to mobile apps
Telegram, Discord, or Signal are current messaging platforms

Who it was for

Kadu was for Polish internet users who wanted to chat on the Gadu-Gadu network without the ads and bloat of the official client. Gadu-Gadu was Poland's MSN Messenger equivalent, dominant through the 2000s. Today the platform has a fraction of its former users, replaced by Messenger, WhatsApp, and Telegram.

Frequently Asked Questions

What was Kadu?

A Polish open source instant messaging client for the Gadu-Gadu network, offering an ad-free alternative to the official GG client with XMPP multi-protocol support.

Is Gadu-Gadu still active?

The platform still exists but has a fraction of its former users. Most Polish users have moved to Messenger, WhatsApp, and Telegram.

What messaging apps are popular in Poland now?

Messenger (Facebook), WhatsApp, and Telegram are the most popular. Discord is growing, especially among younger users.

Features & How-To Guide

#	Feature	How to use
1	Gadu-Gadu protocol support	Configuration › Accounts › Add account › Gadu-Gadu › Enter GG number and password. Fully compatible with the original GG client.
2	Conversation history with search	Right-click a contact › Conversation History. All messages stored in a local database with full-text search.
3	XMPP/Jabber protocol support	Configuration › Accounts › Add account › XMPP. Supports Jabber accounts alongside GG in a single client.
4	Voice conversations 6	Handset button in the chat window (requires VoIP plugin). Voice calls via the GG protocol.
5	Plugin system	Configuration › Plugins. Extend functionality with modules from external developers.
6	Emoticons compatible with GG	Configuration › Appearance › Emoticons. Emoticon sets compatible with the original GG client. Additional packs can be installed.
7	Spam protection	Configuration › Plugins › Anti-spam. Blocks chain messages and unwanted messages.
8	File transfer 2	In the chat window click Send file or drag a file onto the conversation window. Send and receive files.
9	SSL connection encryption	Configuration › Accounts › [GG account] › Connection › Use SSL. Encrypts the connection to the Gadu-Gadu server.
10	OTR message encryption	OTR plugin (Off-the-Record). Right-click a contact › Enable OTR encryption. End-to-end encryption.
11	Send SMS	Contact menu › Send SMS. Send SMS messages to phones directly from the messenger (GG feature).
12	Contact directory search	Tools › Search Directory. Automatic search for users in the public GG directory.