アプリが初回起動かをチェックするメソッド
- (BOOL)isFirstLaunch{ NSUserDefaults*ud = [NSUserDefaults standardUserDefaults]; NSString *key = @"isAlreadyLaunched"; NSString *res = [ud objectForKey:key]; if(! [res isEqual:@"Yes"]){ [ud setObject:@"Yes" forKey:key]; [ud synchronize]; return YES; } return NO; }