using (var _myClient = new HttpClient())
{
    var vUri = new Uri("http://applipodcast.radiofrance.fr/export/podcast.gz");
    using (var response = await _myClient.GetAsync(vUri))
    {
        if (response != null && (response.StatusCode == Windows.Web.Http.HttpStatusCode.Ok ))
        {
            try
            {
                var vBuffer = await response.Content.ReadAsBufferAsync();
                var vArray = vBuffer.ToArray();
            }
            catch (Exception ex)
            {
            }
        }
        else
        {
            string vError = await response.Content.ReadAsStringAsync();
        }
    }
}