对于是否为首次安装的App可以使用如下方法来判断

[[NSUserDefaults standardUserDefaults] boolForKey:@"firstLaunch"];

如果App是通过App Store升级的话可以通过版本号来判断

[[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleVersion"];

 

实际使用可以在didFinishLaunchingWithOptions:中添加如下代码

if(![[NSUserDefaults standardUserDefaults] boolForKey:@"firstLaunch"]) {        [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"firstLaunch"];        NSLog(@"安装之后首次开启App");        //获取当前App版本号并存入NSUserDefaults中        NSString* appVersion = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleVersion"];        NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];        [userDefaults setObject:appVersion forKey:@"appVersion"];        [userDefaults synchronize];    }    else {        //根据版本号判断是否更新后首次启动        NSString* appVersion = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleVersion"];        NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];        NSString* localVersion = [userDefaults stringForKey:@"appVersion"];        if ([appVersion isEqualToString:localVersion]) {            NSLog(@"安装或升级之后并非首次开启App");        }        else {            NSLog(@"升级之后首次开启App");            //将当前App版本号存入NSUserDefaults中            [userDefaults setObject:appVersion forKey:@"appVersion"];            [userDefaults synchronize];        }    }