This fix introduces crash on iPad:
https://bugreports.qt-project.org/browse/QTBUG-23770
I have tried Qt 5.4 beta1 and also backported this to Qt 5.3

The code:
Camera {
id: cam
captureMode: Camera.CaptureStillImage
position: Camera.FrontFace
function next()

{ position = position === Camera.FrontFace ? Camera.BackFace : Camera.FrontFace; }

}

VideoOutput

{ autoOrientation: true source:cam }

MouseArea

{ id: changeCamera onClicked: cam.next() }

MouseArea

{ id: captureButton onClicked: cam.imageCapture.capture() }

Click on changeCamera changes the camera but preview is rotated on 180. Clicking on captureButton causes crash:
program received signal -111, thread:36280;qaddr:3ab80ad0;00:40cc0619;01:e391f32d;02:c0ba0e19;03:f48b7638;04:40cc0619;05:e391f32d;06:01000000;07:a81f9602;08:02000000;09:00000000;0a:00000000;0b:01000000;0c:f4577438;0d:1c1f9602;0e:d135242a;0f:66dfe037;10:30000020;metype:1;mecount:2;medata:1;medata:c;
program received signal -111, thread:36280;qaddr:3ab80ad0;00:40cc0619;01:e391f32d;02:c0ba0e19;03:f48b7638;04:40cc0619;05:e391f32d;06:01000000;07:a81f9602;08:02000000;09:00000000;0a:00000000;0b:01000000;0c:f4577438;0d:1c1f9602;0e:d135242a;0f:66dfe037;10:30000020;metype:1;mecount:2;medata:1;medata:c;
program received signal -111, thread:36280;qaddr:3ab80ad0;00:40cc0619;01:e391f32d;02:c0ba0e19;03:f48b7638;04:40cc0619;05:e391f32d;06:01000000;07:a81f9602;08:02000000;09:00000000;0a:00000000;0b:01000000;0c:f4577438;0d:1c1f9602;0e:d135242a;0f:66dfe037;10:30000020;metype:1;mecount:2;medata:1;medata:c;
program received signal -111, thread:36280;qaddr:3ab80ad0;00:40cc0619;01:e391f32d;02:c0ba0e19;03:f48b7638;04:40cc0619;05:e391f32d;06:01000000;07:a81f9602;08:02000000;09:00000000;0a:00000000;0b:01000000;0c:f4577438;0d:1c1f9602;0e:d135242a;0f:66dfe037;10:30000020;metype:1;mecount:2;medata:1;medata:c;
program received signal -111, thread:36280;qaddr:3ab80ad0;00:40cc0619;01:e391f32d;02:c0ba0e19;03:f48b7638;04:40cc0619;05:e391f32d;06:01000000;07:a81f9602;08:02000000;09:00000000;0a:00000000;0b:01000000;0c:f4577438;0d:1c1f9602;0e:d135242a;0f:66dfe037;10:30000020;metype:1;mecount:2;medata:1;medata:c;
program received signal -111, thread:36280;qaddr:3ab80ad0;00:40cc0619;01:e391f32d;02:c0ba0e19;03:f48b7638;04:40cc0619;05:e391f32d;06:01000000;07:a81f9602;08:02000000;09:00000000;0a:00000000;0b:01000000;0c:f4577438;0d:1c1f9602;0e:d135242a;0f:66dfe037;10:30000020;metype:1;mecount:2;medata:1;medata:c;
hit maximum number of consecutive signals, stopping

The callstack is in AVFImageCaptureControl::capture method in call to captureStillImageAsynchronouslyFromConnection.
I was able to fix this crash with attached patch.
However preview is still rotated.