Cocoa Touch: How To Change UIView’s Border Color And Thickness?

You need to use view’s layer to set border property. e.g:

#import <QuartzCore/QuartzCore.h>
...
view.layer.borderColor = [UIColor redColor].CGColor;
view.layer.borderWidth = 3.0f;

You also need to link with QuartzCore.framework to access this functionality.