影と境界を追加するのは簡単です。
1) Add the QuartzCore framework to your target.
2) Import the framework header in the class where you want to add borders and shadows. (Or if you have custom class for the button then you can simple import this framework in that class.)
3) To add the border to the button use this code (where button is an IBOutlet connected with the button in interface):
[self.button.layer setBorderWidth:3.0];
[self.button.layer setBorderColor:[[UIColor blackColor] CGColor]];
4) To add the shadow to the button use the following code:
[self.button.layer setShadowOffset:CGSizeMake(5, 5)];
[self.button.layer setShadowColor:[[UIColor blackColor] CGColor]];
[self.button.layer setShadowOpacity:0.5];
値を使って遊んで、その動作にどのように影響するかを見ることができます。