These days many popular Linux distributions such as Kubuntu hide the individual applications and only place Kontact prominently.

The initial groupware container application was written in an afternoon by Matthias Hölzer-Klüpfel and later imported into the KDE source repository and maintained by Daniel Molkentin.

At this stage no mail client component existed, so KDE still lacked a functional integrated groupware application.

[7] During the construction of the Kontact application suite, the Kolab groupware server was being worked on by Erfrakon,[8] Intevation.net[9] and Klarälvdalens Datakonsult[10] simultaneously and was completed at approximately the same time.

This work was done as part of the Kroupware[11] project that also involved modifying the KMail and KOrganizer applications to enhance them with additional groupware features.

Additionally, a news component was created from the KNode application by KDE developer Zack Rusin, and Kontact was modified to support an array of mainly web based suites of collaboration software.

Kontact embeds the following KMail supports folders, filtering, viewing HTML mail, and international character sets.

KMail allows manual filtering of spam directly on the mail server, a very interesting feature for dial-up users.

KMail supports the OpenPGP standard and can automatically encrypt, decrypt, sign, and verify signatures of email messages and its attachments via either the inline or OpenPGP/MIME method of signing/encryption.

KMail also supports S/MIME messages as well as Chiasmus,[15] a proprietary cryptographic system created by the German Federal Office for Information Security (BSI).

It integrates with KDE Plasma, allowing interoperability with other KDE programs, including the e-mail client KMail – allowing one-click access to composing an e-mail – and the instant messenger Kopete – showing the online status of and easy access to instant messaging contacts.

It supports multiple NNTP servers, message threads, scoring, X-Face headers (reading and posting), and international character sets.

Also Treeline, an advanced outliner written in Python and personal database available for Linux and Microsoft Windows, has similar functions.