diff --git a/mobile_tools.module b/mobile_tools.module
index 8a3d808..e0265e6 100755
--- a/mobile_tools.module
+++ b/mobile_tools.module
@@ -132,10 +132,18 @@ function mobile_tools_init(){
   // Get current device group for comparison
   $active_device_group = mobile_tools_get_active_device_group();
   
+  $tmp = array();
+  
   // Sort into buckets by weight
   foreach($device_groups as $device_group) {
     $tmp[$device_group->weight][$device_group->dgid] = $device_group;
   }
+  
+  // no device groups then return. 
+  if (!is_array($tmp) || sizeof($tmp == 0)) {
+    return;
+  }
+  
   sort($tmp, SORT_NUMERIC);
   $device_groups = $tmp;