Add SubView with animation.

 myView.alpha=0;

    [mySuperView addSubview:myView];

    [UIView animateWithDuration:0.2
                         animations:^{myView.alpha = 1.0;}
                         completion:nil];

Remove View from SuperView with Animation

[UIView animateWithDuration:0.2
     animations:^{view.alpha = 0.0;}
     completion:^(BOOL finished){ [view removeFromSuperview]; }];