diff --git a/book/forms.rst b/book/forms.rst
index e2767f72e56..72a0e61f186 100644
--- a/book/forms.rst
+++ b/book/forms.rst
@@ -1068,7 +1068,7 @@ that will house the logic for building the task form::
 
         public function getName()
         {
-            return 'task';
+            return 'app_task';
         }
     }
 
@@ -1176,7 +1176,7 @@ easy to use in your application.
             app.form.type.task:
                 class: AppBundle\Form\Type\TaskType
                 tags:
-                    - { name: form.type, alias: task }
+                    - { name: form.type, alias: app_task }
 
     .. code-block:: xml
 
@@ -1188,7 +1188,7 @@ easy to use in your application.
 
             <services>
                 <service id="app.form.type.task" class="AppBundle\Form\Type\TaskType">
-                    <tag name="form.type" alias="task" />
+                    <tag name="form.type" alias="app_task" />
                 </service>
             </services>
         </container>
@@ -1202,7 +1202,7 @@ easy to use in your application.
                 'AppBundle\Form\Type\TaskType'
             )
             ->addTag('form.type', array(
-                'alias' => 'task',
+                'alias' => 'app_task',
             ))
         ;
 
diff --git a/cookbook/form/create_custom_field_type.rst b/cookbook/form/create_custom_field_type.rst
index 91dfe580c5e..d4434f2929d 100644
--- a/cookbook/form/create_custom_field_type.rst
+++ b/cookbook/form/create_custom_field_type.rst
@@ -311,14 +311,14 @@ the ``genders`` parameter value as the first argument to its to-be-created
                 arguments:
                     - "%genders%"
                 tags:
-                    - { name: form.type, alias: gender }
+                    - { name: form.type, alias: app_gender }
 
     .. code-block:: xml
 
         <!-- src/AppBundle/Resources/config/services.xml -->
         <service id="app.form.type.gender" class="AppBundle\Form\Type\GenderType">
             <argument>%genders%</argument>
-            <tag name="form.type" alias="gender" />
+            <tag name="form.type" alias="app_gender" />
         </service>
 
     .. code-block:: php
@@ -332,7 +332,7 @@ the ``genders`` parameter value as the first argument to its to-be-created
                 array('%genders%')
             ))
             ->addTag('form.type', array(
-                'alias' => 'gender',
+                'alias' => 'app_gender',
             ))
         ;
 
diff --git a/cookbook/form/create_form_type_extension.rst b/cookbook/form/create_form_type_extension.rst
index 75c5d0a63db..5666c689e89 100644
--- a/cookbook/form/create_form_type_extension.rst
+++ b/cookbook/form/create_form_type_extension.rst
@@ -312,7 +312,7 @@ next to the file field. For example::
 
         public function getName()
         {
-            return 'media';
+            return 'app_media';
         }
     }
 
diff --git a/cookbook/form/dynamic_form_modification.rst b/cookbook/form/dynamic_form_modification.rst
index 50e8df4c25d..0a73b9d5d8f 100644
--- a/cookbook/form/dynamic_form_modification.rst
+++ b/cookbook/form/dynamic_form_modification.rst
@@ -240,7 +240,7 @@ Using an event listener, your form might look like this::
 
         public function getName()
         {
-            return 'friend_message';
+            return 'app_friend_message';
         }
     }
 
@@ -388,7 +388,7 @@ it with :ref:`dic-tags-form-type`.
                 class: AppBundle\Form\Type\FriendMessageFormType
                 arguments: ["@security.token_storage"]
                 tags:
-                    - { name: form.type, alias: friend_message }
+                    - { name: form.type, alias: app_friend_message }
 
     .. code-block:: xml
 
@@ -396,7 +396,7 @@ it with :ref:`dic-tags-form-type`.
         <services>
             <service id="app.form.friend_message" class="AppBundle\Form\Type\FriendMessageFormType">
                 <argument type="service" id="security.token_storage" />
-                <tag name="form.type" alias="friend_message" />
+                <tag name="form.type" alias="app_friend_message" />
             </service>
         </services>
 
@@ -404,7 +404,7 @@ it with :ref:`dic-tags-form-type`.
 
         // app/config/config.php
         $definition = new Definition('AppBundle\Form\Type\FriendMessageFormType');
-        $definition->addTag('form.type', array('alias' => 'friend_message'));
+        $definition->addTag('form.type', array('alias' => 'app_friend_message'));
         $container->setDefinition(
             'app.form.friend_message',
             $definition,
@@ -420,7 +420,7 @@ access to the form factory, you then use::
     {
         public function newAction(Request $request)
         {
-            $form = $this->get('form.factory')->create('friend_message');
+            $form = $this->get('form.factory')->create('app_friend_message');
 
             // ...
         }
@@ -428,14 +428,14 @@ access to the form factory, you then use::
 
 If you extend the ``Symfony\Bundle\FrameworkBundle\Controller\Controller`` class, you can simply call::
 
-    $form = $this->createForm('friend_message');
+    $form = $this->createForm('app_friend_message');
 
 You can also easily embed the form type into another form::
 
     // inside some other "form type" class
     public function buildForm(FormBuilderInterface $builder, array $options)
     {
-        $builder->add('message', 'friend_message');
+        $builder->add('message', 'app_friend_message');
     }
 
 .. _cookbook-form-events-submitted-data: