Some questions about license
I program in the Qt open source
1)Can i dont open the source code
2)Can i sell my program
3)Under what license can I distribute my program
Advance many thanks for your consult
"This":http://developer.qt.nokia.com/search/tag/licensing and "this":http://developer.qt.nokia.com/search/tag/license should give you an overview of the topic.
You should look into using the LGPL licence.
If I have made my own app using Qt, do I need to include any kind of licensing documents in my "About" section ?
Did you read the licence you were using to build your application in the first place? What licence was that? What does it say on this topic?