private void unregisterApps(Set<String> apps) {
   Set<String> unregisteringApps =
       ApeicPrefsUtil.getInstance(this).getStringSetPref(ApeicPrefsUtil.KEY_UNREGISTERING_APPS);
   for (String app : apps) {
     HttpClient client = new DefaultHttpClient();
     HttpGet get =
         new HttpGet(
             API_PREFIX
                 + "/"
                 + ApeicPrefsUtil.getInstance(this).getAndroidID()
                 + "/"
                 + SUFFIX_UNREGISTER
                 + "?app="
                 + app);
     try {
       HttpResponse response = client.execute(get);
       int statusCode = response.getStatusLine().getStatusCode();
       Log.d(
           ApeicUtil.TAG_HTTP,
           "Status code of unregistering " + app + ": " + String.valueOf(statusCode));
       if (statusCode == 200) {
         if (unregisteringApps.contains(app)) {
           unregisteringApps.remove(app);
         }
       } else {
         unregisteringApps.add(app);
       }
     } catch (IOException e) {
       Log.e(ApeicUtil.TAG_HTTP, e.getMessage());
       unregisteringApps.add(app);
     }
   }
   ApeicPrefsUtil.getInstance(this)
       .setStringSetPref(ApeicPrefsUtil.KEY_UNREGISTERING_APPS, unregisteringApps);
 }
    @Override
    protected void onHandleIntent(Intent intent) {
      Log.v(ApeicUtil.TAG_HTTP, "UpdateInstalledAppsIntentService onHandleIntent");

      PackageManager pm = getPackageManager();
      Set<String> currInstalledApps = new HashSet<String>();
      for (ApplicationInfo info : pm.getInstalledApplications(PackageManager.GET_META_DATA)) {
        if (pm.getLaunchIntentForPackage(info.packageName) != null) {
          currInstalledApps.add(info.packageName);
        }
      }

      ApeicPrefsUtil prefsUtil = ApeicPrefsUtil.getInstance(this);
      Set<String> registeringApps = prefsUtil.getStringSetPref(ApeicPrefsUtil.KEY_REGISTERING_APPS);
      if (registeringApps.size() > 0) {
        Log.v(ApeicUtil.TAG_HTTP, "Re-update newly installed apps.");
        registerApps(prefsUtil.getStringSetPref(ApeicPrefsUtil.KEY_REGISTERING_APPS));
      }
      Set<String> unregisteringApps =
          prefsUtil.getStringSetPref(ApeicPrefsUtil.KEY_REGISTERING_APPS);
      if (unregisteringApps.size() > 0) {
        Log.v(ApeicUtil.TAG_HTTP, "Re-update uninstalled installed apps.");
        unregisterApps(prefsUtil.getStringSetPref(ApeicPrefsUtil.KEY_UNREGISTERING_APPS));
      }

      if (prefsUtil.getPrefs().contains(ApeicPrefsUtil.KEY_INSTALLED_APPS)) {
        Set<String> lastInstalledApps =
            prefsUtil.getStringSetPref(ApeicPrefsUtil.KEY_INSTALLED_APPS);
        Set<String> newlyInstalledApps =
            getNewlyInstalledApps(currInstalledApps, lastInstalledApps);
        if (newlyInstalledApps.size() > 0) {
          Log.v(ApeicUtil.TAG_HTTP, "Newly installed Apps: ");
          registerApps(newlyInstalledApps);
        }

        Set<String> removedApps = getUninstalledApps(currInstalledApps, lastInstalledApps);
        if (removedApps.size() > 0) {
          Log.v(ApeicUtil.TAG_HTTP, "Uninstalled Apps: ");
          unregisterApps(removedApps);
        }
      } else {
        Log.v(ApeicUtil.TAG_HTTP, "Current installed Apps: ");
        registerApps(currInstalledApps);
      }

      ApeicPrefsUtil.getInstance(this)
          .setStringSetPref(ApeicPrefsUtil.KEY_INSTALLED_APPS, currInstalledApps);
    }
 private String getUploadUrl() {
   return API_PREFIX
       + "/"
       + ApeicPrefsUtil.getInstance(this).getAndroidID()
       + "/"
       + SUFFIX_UPLOAD;
 }