Change the color of the NavigationBar for the “More” tab

self.tabBarController.moreNavigationController.navigationBar.barStyle = UIBarStyleBlackOpaque;

Change the title of the current (selected) UITabBarItem

[[self.tabBarController.viewControllers objectAtIndex:self.tabBarController.selectedIndex] setTitle:@"Your Title"];

Iterate through UITabBar items

for (UITabBarItem *item in self.tabBarController.viewControllers) {
    // do something
}