Based on this answer: http://stackoverflow.com/a/6134327/1211664.

animation bounce view

popUp.transform = CGAffineTransformScale(CGAffineTransformIdentity, 0.001, 0.001);

[self.view addSubview:popUp];

[UIView animateWithDuration:0.3/1.5 animations:^{
    popUp.transform = CGAffineTransformScale(CGAffineTransformIdentity, 1.1, 1.1);
} completion:^(BOOL finished) {
    [UIView animateWithDuration:0.3/2 animations:^{
        popUp.transform = CGAffineTransformScale(CGAffineTransformIdentity, 0.9, 0.9);
    } completion:^(BOOL finished) {
        [UIView animateWithDuration:0.3/2 animations:^{
            popUp.transform = CGAffineTransformIdentity;                            
        }];
    }];
}];