Custom iOS6 UI to like iOS7

Custom_iOS6_UI

    [[UIBarButtonItem appearance] setBackgroundImage:[UIImage new]
                                            forState:UIControlStateNormal
                                          barMetrics:UIBarMetricsDefault];
    
    [[UINavigationBar appearance] setTitleTextAttributes:@{
                                                           NSForegroundColorAttributeName: [UIColor blackColor],
                                                           NSFontAttributeName: [UIFont systemFontOfSize:17],
                                                           UITextAttributeTextShadowOffset: [NSValue valueWithUIOffset:UIOffsetZero]
                                                           }];
    
    [[UIBarButtonItem appearance] setTitleTextAttributes:@{
                                                           UITextAttributeFont: [UIFont systemFontOfSize:17],
                                                           UITextAttributeTextShadowOffset: [NSValue valueWithUIOffset:UIOffsetZero]
                                                           }
                                                forState:UIControlStateNormal];

    [[UITabBar appearance] setBackgroundImage:[UIImage imageWithColor:[UIColor gray225]]];
    [[UITabBar appearance] setSelectionIndicatorImage:[UIImage new]];
    
    //Custom back button image for iOS6 & iOS7
    [[UIBarButtonItem appearance] setBackButtonBackgroundImage:[[UIImage imageNamed:@"icon_tabbar_back"] resizableImageWithCapInsets:UIEdgeInsetsMake(0, 18, 0, 0)]
                                                      forState:UIControlStateNormal
                                                    barMetrics:UIBarMetricsDefault];
    //Hide back button title for iOS6 & iOS7
    [[UIBarButtonItem appearance] setBackButtonTitlePositionAdjustment:UIOffsetMake(0, -60)
                                                         forBarMetrics:UIBarMetricsDefault];