Qt Development Frameworks

Qt Development Frameworks is a division of Digia, which produces through the acquisition of the Norwegian software company Trolltech, which programming environments and libraries, in 2008, was created by Nokia. Trolltech (formerly Quasar Technologies ) was developed by Haavard Nord and Eirik Chambe -Eng (both co-CEO ) founded in 1994 and was listed from 2006 to 2008 on the Oslo Stock Exchange. In 2012 it was sold to the Finnish software company Digia.


The development of the main product " Qt " began in 1992. Two years later the company Trolltech in Oslo, Norway was founded. In 1996, the European Space Agency 's first customer, she used both Qt / Windows and Qt/X11. In June 1998, Trolltech signed a statement that the "KDE Free Qt Foundation " (represented by the KDE eV ) the availability of a free version of the Qt toolkit ( " Qt Free Edition " ) promised. If Trolltech set the development of the free version or deliver more than twelve months no update, so the KDE Free Qt Foundation would have the right to provide the information available at that moment source code under the BSD license.

In the following two years branches were in Brisbane (1999, Australia) and Santa Clara (2000, USA). In October of the same year Trolltech also changed the licensing model of Qt 2.2 and all subsequent versions: It is now subject to the provisions of the "GNU General Public License" (GPL ) and the " Qt Public License " ( QPL ). Qt is now dual - licensed and fully complies with the conditions for free software, however, were not all components relizenziert: Qt / Windows is not it fell under the new rules and stayed with costs for all developers. 2002 new products Qtopia and Qt / Mac appeared. The following year, Qt / Mac was placed under the GPL and the new product team builder ( a tool for parallel and distributed compilation of written in C or C source code in networks) published. With Qt Solutions, a new development department for commercial customers was, where he developed solutions can be found occasionally with strong delayed input in Qt. In July 2004, the agreement with the KDE Free Qt Foundation was renewed.

A year later the branch was founded in China and Trolltech announced that with the release of Qt version 4.0 and the Windows port will be placed under the GPL. After the release of the first stable release on 28 June 2005, the number of based on Qt open source projects increased, the KDE team began porting to Qt4 and KDE announced for the end product "KDE SC 4 " a variety new functions. Opened in 2006, Trolltech has offices in Berlin and Munich.

In July 2006, Trolltech went under the ticker symbol TROLL on the Oslo Stock Exchange. The issue price was € 17.50 and rose on the same day on over 21 €, in the following months, however, the stock had lost considerable value and the price fell below the issue value.

On June 17, 2008 Trolltech was acquired by Nokia on 29 September 2008 and renamed in Qt software. Since 18 June 2008, the former Trolltech is no longer listed on the Oslo Stock Exchange. Since 11 August 2009, the division is now called Qt Development Frameworks.

On 14 January 2009, Qt was added 4.5 and following the license "GNU Lesser General Public License " (LGPL ).

In March 2011, the business part, which deals with the licensing and service for about 3500 customers, was sold by Nokia in the Finnish software company Digia. A month earlier, it was revealed that Nokia will not use the Qt software for its future Nokia Windows Phones.

In August 2012, Digia Qt has completely taken over by Nokia and it paid 4 million euros.


  • Qt (library ) - the main product, a program library including development environment for cross-platform software development. The programs are primarily written in C and can be run on other Unix / Linux, Microsoft Windows and Macintosh. Major parts of KDE based on Qt, as Google Earth and Skype.
  • Qt Creator - a C based cross-platform development environment for Qt.
  • Qt Extended ( formerly Qtopia ) - a graphical interface for PDAs, mobile phones and other embedded devices. In her free PDA - based surface OPIE. The development was stopped and the functional under the name Qt Mobility integrated into Qt.
  • QtScript - a cross-platform toolkit for the implementation of scripting capabilities in Qt programs (formerly implemented by Qt Script for Applications ( QSA ) ).
  • qmake - a make- descendant to create a software project, similar to automake.
  • Team Builder - enables distributed compilation of written in C or C code.
  • Green Phone - a system based on Qtopia mobile phone, which served only to product demonstration, in contrast to the Neo1973.

Corporate Structure

The last 238 employees (as of September 2007) held by the end of January 2008, the largest shares of the company. Trolltech supports open source projects, most notably the KDE project, through support, developer programs, programming contests and paid software developers.

On 28 January 2008 Trolltech announced the sale to Nokia in a statement. The purchase offer of 843.6 million kroner ( about 105 million euros ) was approved by Trolltech board and binding supported by shareholders with more than two-thirds of the shares. The listing of the company ended in June 2008.


Employees are a so-called Creative Friday conceded every Friday before starting to work on a project during working hours, which has nothing to do directly with Trolltech - A condition is however an informal review by the management.

Many current and former Trolltech employees come from the open source environment and are still working for such projects:

  • Ettrich, founder of the KDE project, Director of Software Development for Qt
  • Scott Collins, a former developer at Mozilla
  • Harri Porten, KDE developer and CEO of froglogic
  • Zack Rusin, developers in the X.Org project ( worked until August 2007 for Trolltech )
  • Roberto Raggi, KDevelop developers
  • Benjamin Meyer, KDE developers
  • Knut Yrvin, skolelinux
  • Lars Knoll, KHTML architect rose in December 2007 as head of development
  • Aaron Joseph Seigo, KDE desktop developers (plasma)