@iphone_dev_jp @econa77 簡単な処理なら

UIImageViewのサブクラスで以下をオーバーライドとか

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    //imageView をドラッグするサンプル
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint location = [touch locationInView:[touch.view superview]];
    self.center = location;
}