AppController.mm

static AppDelegate s_sharedApplication;

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    // request
    NSURL *url = [NSURL URLWithString:@"http://xxx.appspot.com/"];
    NSURLRequest *request = [NSURLRequest requestWithURL:url
                                             cachePolicy:NSURLRequestReloadIgnoringLocalCacheData //キャッシュ無視
                                         timeoutInterval:30];
    NSURLResponse *response = nil;
    NSError *error = nil;
    NSData *data = [
                    NSURLConnection
                    sendSynchronousRequest : request
                    returningResponse : &response
                    error : &error
                    ];

    if(response){
        NSLog(@"%@", response);
    } else {
        NSString *error_str = [error localizedDescription];
        NSLog(@"通信エラー%@", error_str);
    }