With Qt Quick, rapid application development for mobile devices became possible, while logic can still be written with native code as well to achieve the best possible performance. Qt also provides Qt Quick, that includes a declarative scripting language called QML that allows using JavaScript to provide the logic. Qt supports various compilers, including the GCC C++ compiler, the Visual Studio suite, PHP via an extension for PHP5, and has extensive internationalization support. An example of such a non-GUI program using Qt is the Cutelyst web framework. Non-GUI programs can also be developed, such as command-line tools and consoles for servers. Most GUI programs created with Qt have a native-looking interface, in which case Qt is classified as a widget toolkit. To be safe it would be best not to distribute the GPL components at all together with your application.Qt is used for developing graphical user interfaces (GUIs) and multi-platform applications that run on all major desktop platforms and most mobile or embedded platforms. If you don't want to release the source code of your whole application, you must avoid distributing GPL applications in a way that combines it with your application. Note that some components of the Qt framework may be GPL licensed, and not LGPL. Basically, the LGPL requires that you document the process for replacing your version of the LGPL library (Qt) with another version that the user may have built herself.
In practice it also means that on platforms like iOS and Android, LGPL is not really usable (because these platforms apparently do not allow users to replace the libraries with another version). on Windows, the Qt libraries must be DLLs, and on Linux the libraries for Qt must be. In practice this means that you must use dynamically linked libraries for the LGPL library (i.e.
Make it possible for a user to use a different version of that LGPL library with your application. the Qt libraries), and also that you allow your users to replace the LGPL libraries with alternative versions.īasically what this has been interpreted to mean is that if you distribute LGPL libraries (such as Qt) with your application, then you also must:ĭistribute to your users the source code of the same version of that library, or make it available in a way that is conformant with the LGPL license. Namely, the obligation for the LGPL is that you distribute the source code of the LGPL libraries themselves (i.e.
Note that the terminology "commercial license" is a bit ambiguous, because the (L)GPL license also allows 'commercial' use as long as you can follow the obligations.
My question is, do I need a commercial license for the framework even though I don't want to sell the software and the source code is free for all employees of the corporation?Īs long as you can comply with the (L)GPL requirements of the Qt libraries, then you do not need to purchase a "commercial license" from the Qt Company.