As QtCreator 2.2 is coming out, we have started working on new experimental features in a new branch. The latest of them is the Qml Perfomance Monitor.
This little tool, part of the new Analyze Mode, can be used to profile your Qt Quick applications. With it you can inspect binding evaluations, signal handling, and painting operations when running your Qml code. This is very useful for identifying potential bottlenecks, specially in the evaluation of bindings. I leave you with a little video introducing the feature.
In the video, Qml Perfomance Monitor is tested against a Qt Quick Application created with QtCreator's wizard by importing Qt's samegame demo.
This new tool was possible thanks to the Brisbane Trolls who started this small project. Be aware that this is still a experimental feature in its very early stages. Lots of functionality is still missing, and it might even have stability issues. As they say in these cases, try at your own risk.
I would also like to mention that profiling on device is possible by launching your Qt Quick application with the commandline parameters "-qmljsdebugger=port:33456" and then attaching the profiler to the running application using the options in the Debug menu under Start Analyzer. That being said, I can't guarantee that it works in all cases, we still have to test it thoroughfully.
For feedback/questions, please contact us on IRC at the freenode server, channel #qt-creator.