[fieldju]

Is it possible to store call back functions in a helper file or is it required that they be in a controller?

[kenvogt]

What matters is that your callback functions can be reached with $this->your_function_name() from your controller.

[web-johnny]

Yeap you can easily call them like this:

$crud->callback_edit_field('phone','edit_field_callback_1');

where edit_field_callback_1 is a function from your helper. For more about callbacks you can read http://php.net/manual/en/function.call-user-func.php