diff --git a/NetBiblio.php b/NetBiblio.php
index e1b9ad6..e8c70dc 100644
--- a/NetBiblio.php
+++ b/NetBiblio.php
@@ -136,7 +136,8 @@ class NetBiblio extends WebService
 
             // add fields for mobile apps compatibility
             $b['date'] = date('Y.m.d', strtotime($b['availabilityDate']));
-            $b['readBy'] = isset($b['reader']) ? $b['reader'] : null;
+            $b['readBy'] = isset($b['reader']) ? $b['reader'] : 'Lecteur inconnu';
+            $b['category'] = $b['genre'];
             $b['code3'] = $b['producerCode'];
             $b['code3Long'] = $b['producer'];
             $b['typeMedia1'] = $b['mediaType'];
@@ -529,7 +530,7 @@ class NetBiblio extends WebService
 
         $data = array();
         foreach($books as $b) {
-            $data[$b['genre']][] = $b;
+            $data[$type][] = $b;
         }
         return $data;
     }