Changing the Tint Color of UIBarButtonItem

In iOS 7, to set the color of all barButtonItems in your app, set the tintColor property on the application's window in the AppDelegate.

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window.tintColor = [UIColor whiteColor];
    return YES;
}

More detailed info in Apple's iOS 7 UI Transition Guide (Specifically under the 'Using Tint Color` section).

***OR***

Based on some of the comments, you can also achieve this with the UINavigationBar appearance proxy. This will affect the tintColor of only UIBarButtonItems, as opposed to setting the tintColor on the window and affecting all subviews of that window.

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    if([UINavigationBar conformsToProtocol:@protocol(UIAppearanceContainer)]) {
        [UINavigationBar appearance].tintColor = [UIColor whiteColor];
    }

    return YES;
}

I think you are looking for a property of your UINavigationBar. Try setting self.navigationController.navigationBar.tintColor = [UIColor whiteColor];

See "Appearance of Navigation Bars" section: https://developer.apple.com/library/ios/documentation/userexperience/conceptual/UIKitUICatalog/UINavigationBar.html#//apple_ref/doc/uid/TP40012857-UINavigationBar-SW1