How to design for different screen sizes, so that widgets would take up maximum screen size? Should i use sizePolicy ? If so what values (Ignored does not seem to help). What about font sizes? And styling with css : lots of examples with pixels, but 100px is not the same on N95 or 5800 express music. Create different UI file for different resolutions? Is that possible with QT designer? Detect screen size, and resize widgets accordingly ?