title: Check if an app already exists in Android market via API
body: <p>This Android market API has a method <code>isInMarket()</code>. Can I use this method to check if an app already exists in the Android market?</p>
  
  <pre><code>AppInfo mAppInfo = new AppInfo("packagename.example");
  if (!mAppInfo.isInMarket()) {
      //app non-exist in the android market
  } 
  else {
      //app exist in the android market
  }
  </code></pre>
  
  <p>I tested this code in an emulator but it doesn't work. How can I make it work?</p>