Canonical will include Nokia's Qt toolkit as a standard piece in future iterations of Ubuntu.

This step will enable applications built with Qt to become part of the Linux distribution, said Mark Shuttleworth, founder of Canonical, in a blog on Tuesday. The announcement does not include Ubuntu 11.04 -- aka Natty Narwhal -- which is scheduled for final release in April, according to Canonical.

"As part of our planning for Natty+1, we'll need to find some space on the CD for Qt libraries, and we will evaluate applications developed with Qt for inclusion on the CD and default install of Ubuntu," Shuttleworth said.

Qt, developed by Trolltech and acquired by Nokia in 2008, is a cross-platform development kit and user interface framework used by approximately 350,000 developers including commercial developers such as Adobe, Amazon, Autodesk, Google, and Skype.

The kit lets developers write Web-enabled applications once, then deploy them across desktop, mobile, and embedded operating systems without rewriting the source code, according to Nokia. Qt-developed apps can be deployed across Linux, Mac, Windows, Symbian, and MeeGo operating systems. The latest version of Qt includes a widget toolkit, a pre-processing tool that extends the C++ programming language, and an expansive set of libraries. It also features Qt Quick, a framework designed to speed the development of mobile user interfaces that span multiple form factors and platforms, Nokia said.

Traditionally, developers have created written Linux desktop applications using Gtk+ or Qt, with GNOME-based distribution Ubuntu historically allying itself with Gtk+. Canonical is working with dconf expert Ryan Lortie to develop dconf bindings for Qt, said Shuttleworth.

"The decision to be open to Qt is in no way a criticism of GNOME. It's a celebration of free software's diversity and complexity. Those values of ease of use and integration remain shared values with GNOME, and a great basis for collaboration with GNOME developers and project members. Perhaps GNOME itself will embrace Qt, perhaps not, but if it does then our willingness to blaze this trail would be a contribution in leadership," Shuttleworth said. "It's much easier to make a vibrant ecosystem if you accept a certain amount of divergence from the canonical way, so to speak. Our work on design is centered around GNOME, with settings and preferences the current focus as we move to GNOME 3.0 and Gtk3."

Last fall, Nokia upgraded the kit to Qt 4.7, which is the standard toolkit for MeeGo.