MyImage.alpha = 1.0f;
[UIView animateWithDuration:0.1f                     //speed of flash
                      delay:0.0f
                    options:UIViewAnimationOptionAutoreverse
                 animations:^ {
       [UIView setAnimationRepeatCount:4.0f/2.0f];   //flash few times
       MyImage.alpha = 0.0f;
} completion:^(BOOL finished) {
       [MyImage removeFromSuperview];
}];