In order to integrate sendy with many systems, we need to make a cross domain ajax request. The problem is that cross domain plain text responses are not allowed by browsers: "Origin 'url' is not allowed by Access-Control-Allow-Origin".
But this can be solved using the ?callback= ajax argument or simply providing JSONP response support at Sendy.co API.
With this support, we can most efficiently build forms/integration from sendy api to our systems and forms.
Reffer: http://api.jquery.com/jQuery.ajax/
http://stackoverflow.com/questions/5537297/ios-how-to-perform-a-http-post-request
http://sanjoyinfoworld.blogspot.in/2012/10/cross-site-ajax-request.html