remove 1px bottom line of the navigation bar

remove-bottom-line-navbar.md

If you just want to use a solid navigation bar color and have set this up in your storyboard, use this code in your AppDelegate class to remove the 1 pixel border via the appearance proxy:

[[UINavigationBar appearance] setBackgroundImage:[[UIImage alloc] init]
                                  forBarPosition:UIBarPositionAny
                                      barMetrics:UIBarMetricsDefault];

[[UINavigationBar appearance] setShadowImage:[[UIImage alloc] init]];

swift

navigationController?.navigationBar.setBackgroundImage(UIImage(), forBarPosition: .Any, barMetrics: .Default)
navigationController?.navigationBar.shadowImage = UIImage()