title: How to validate paid iOS app
body: <p>I'm going to deploy new paid app to appstore. This app will connect to our server and download some data (pretty big sometimes). </p>
  
  <p>I'd like to know, is there any way I can check (on server side), that request is going from app, which was really paid (not stolen).</p>
  
  <p>I know that anybody can buy app once and then distribute it (and guys with jailbreaked phones/pads can install it easily). It may cause extra traffic from our servers, and we want to protect us from it.</p>
  
  <p>Or may be I can somehow figure out, that request comes from one sold copy of app? In this case, I can restrict numbers of downloads from one copy, so if it will be widely distributed, it just stops works one day.</p>
  
  <p>Any ideas?</p>