You could simply set the center point of the UIImageView before you rotate it?
Code:
//create rect
UIImageView *myImageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"my_image.png"]];
//set point of rotation
myImageView.center = CGPointMake(100.0, 100.0);
//rotate rect
myImageView.transform = CGAffineTransformMakeRotation(3.14159265); //rotation in radians
Give that a bash, hope it helps
