1、创建window分类
2、沙盒进行版本判断
3、新特性控制器切换

创建window分类，判断版本

#import "UIWindow+ALExtension.h"
#import "ALTabBarViewController.h"
#import "ALNewViewController.h"

@implementation UIWindow (ALExtension)

- (void)switchRootViewController {
    
    // 之前已经登录成功过
    NSString *key = @"CFBundleVersion";
    // 上一次的使用版本(存储在沙盒中的版本号)
    NSString *lastVersion = [[NSUserDefaults standardUserDefaults] objectForKey:key];
    
    // 当前软件的版本号（info.plist中获得）
    NSString *currentVersion = [NSBundle mainBundle].infoDictionary[key];
    
    if ([currentVersion isEqualToString:lastVersion]) {
        // 版本相同,这次打开和上次打开是同一个版本
        self.rootViewController =  [[ALTabBarViewController alloc] init];
        
    } else {
        // 这次打开的和上一次不一样
        self.rootViewController = [[ALNewViewController alloc] init];
        
        // 将当前的版本号存进沙盒
        [[NSUserDefaults standardUserDefaults]setObject:currentVersion forKey:key];
        // 马上同步到沙盒
        [[NSUserDefaults standardUserDefaults] synchronize];
    }
    
}

新特性控制器

#import "ALNewViewController.h"
#import "ALTabBarViewController.h"

#define KWidth self.view.frame.size.width
#define KHeight self.view.frame.size.height
#define ALNewCount 4

@interface ALNewViewController () <UIScrollViewDelegate>

@property (weak, nonatomic) IBOutlet UIScrollView *scrollView;

@property (weak, nonatomic) IBOutlet UIPageControl *pageControl;


@end

@implementation ALNewViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    // 创建图片
    for (int i = 0; i < ALNewCount; i++) {
        
        UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(i * KWidth, 0, KWidth, KHeight)];
        imageView.image = [UIImage imageNamed:[NSString stringWithFormat:@"workth0%d", i + 1]];
        
        [self.scrollView addSubview:imageView];
        
        if (i == ALNewCount - 1) {
            [self setupLastImageView:imageView];
        }
        
    }
    
    self.pageControl.numberOfPages = ALNewCount;
    
    self.scrollView.contentSize = CGSizeMake(ALNewCount * KWidth, 0);
    
    
}

#pragma mark - 进入主界面
- (void)setupLastImageView:(UIImageView *)imageView {
    
    // 开启用户交互
    imageView.userInteractionEnabled = YES;
    
    UIButton *enter = [[UIButton alloc] init];
    enter.frame = CGRectMake(0, KHeight - 100, KWidth, 30);
    [enter setTitle:@"进入阿里星球之旅" forState:UIControlStateNormal];
    [enter setBackgroundImage:[UIImage imageNamed:@"nav_bg"] forState:UIControlStateNormal];
    
    [imageView addSubview:enter];
    [enter addTarget:self action:@selector(startClick) forControlEvents:UIControlEventTouchUpInside];
    
    
}

// 切换
- (void)startClick {
    UIWindow *window = [UIApplication sharedApplication].keyWindow;
    window.rootViewController = [[ALTabBarViewController alloc] init];
}

#pragma UIScrollViewDelegate
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {

    self.pageControl.currentPage =  (int)(scrollView.contentOffset.x / scrollView.frame.size.width + 0.5);
    
    
}