Używam AFHTTPRequestOperationManager do wysyłania niektórych JSON na mój serwer, mój kod jest poniżej.

NSDictionary *parameters = [[NSDictionary alloc] initWithObjectsAndKeys:@"john", @"name", @"[email protected]", @"email", @"xxxx", @"password", @"1", @"type", nil];
// Do any additional setup after loading the view.
AFSecurityPolicy *policy = [[AFSecurityPolicy alloc] init];
[policy setAllowInvalidCertificates:YES];
AFHTTPRequestOperationManager *operationManager = [AFHTTPRequestOperationManager manager];
[operationManager setSecurityPolicy:policy];

[operationManager POST:@"posturl here" parameters:parameters success:^(AFHTTPRequestOperation *operation, id responseObject) {
    NSLog(@"JSON: %@", [responseObject description]);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
    NSLog(@"Error: %@", [error description]);
}];

a odpowiedź jest następująca:

2013-11-18 16:49:29.780 SwapOnceApiTester[12651:60b] Error: Error Domain=AFNetworkingErrorDomain Code=-1011 "Request failed: unsupported media type (415), got 1664256" UserInfo=0x1565a6c0 {NSErrorFailingURLKey=xxxxxxx, AFNetworkingOperationFailingURLResponseErrorKey=<NSHTTPURLResponse: 0x15656db0> { URL: xxxxxxxxx } { status code: 415, headers {
    "Cache-Control" = "max-age=604800";
    Connection = "keep-alive";
    "Content-Type" = "application/json";
    Date = "Mon, 18 Nov 2013 11:49:28 GMT";
    Expires = "Mon, 25 Nov 2013 11:49:28 GMT";
    Server = nginx;
    "Transfer-Encoding" = Identity;
    "X-Powered-By" = PleskLin;
} }, NSLocalizedDescription=Request failed: unsupported media type (415), got 1664256}

Nie wiem, z czym jest problem.