public static async Task<string> Connect(string email, string password, byte[] data)
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri + "user/connect?");
            request.Method = HttpMethod.Post;
            request.ContentType = "application/x-www-form-urlencoded";

        // Don't works because GetRequestStream() don't exists...
            //using (var writer = new StreamWriter(request.GetRequestStream()))
            //{
            //    writer.Write("field=value");
            //}

            HttpWebResponse response = (HttpWebResponse)await request.GetResponseAsync();
            using (var sr = new StreamReader(response.GetResponseStream()))
            {
//                Debug.WriteLine(sr.ReadToEnd());
                return sr.ReadToEnd();
            }
        }