In the page you sent the trigger for the upload behave iOS at line 70:
if($WA_DFP_UploadStatus["WA_UploadResult1"]["statusCode"] == 1){
This is the code that means upload file success.
the code for Any Form Post would be:
if($_SERVER['REQUEST_METHOD'] == "POST"){
I'll need to troubleshoot directly, see the private message section.