UITextField Only Top And Bottom Border

One approach I have found works good is using layers. Here's a snippet:

CALayer *bottomBorder = [CALayer layer];
bottomBorder.frame = CGRectMake(0.0f, self.frame.size.height - 1, self.frame.size.width, 1.0f);
bottomBorder.backgroundColor = [UIColor blackColor].CGColor;
[myTextField.layer addSublayer:bottomBorder];

Hope this helps someone.

@user3075378's great & simple example in Swift

var bottomBorder = CALayer()
bottomBorder.frame = CGRectMake(0.0, textField.frame.size.height - 1, textField.frame.size.width, 1.0);
bottomBorder.backgroundColor = UIColor.blackColor().CGColor
textField.layer.addSublayer(bottomBorder)