multi-touch not working
I'm trying to support multi-touch with a QWidget based app but although I can control the UI elements by touching, multi-touch is not working. The documentation is quite clear on what to do (http://doc.qt.io/qt-5/qtouchevent.html) and I don't think I missed a point. I've also tested with the Qt simple dials example (in Qt5.5.1/Examples/Qt-5.5/touch/dials), without more success.
Note that I've another app, but based on QGraphicsItem, where multi-touch works perfectly.
I'm using Qt5.5.1 on MacOS 10.10.5. I've run the tests on iOS and Android as well with the same result. Note that the QGraphicsItem app works correctly on these devices.
Any idea of what could be wrong?