diff --git a/bootstrap/__init__.py b/bootstrap/__init__.py
index d5e18e1..07f0e9e 100644
--- a/bootstrap/__init__.py
+++ b/bootstrap/__init__.py
@@ -1,3 +1 @@
 __version__ = "5.3.2"
-
-default_app_config = 'bootstrap.apps.BootstrapConfig'
diff --git a/bootstrap/apps.py b/bootstrap/apps.py
index 359806f..4654e52 100644
--- a/bootstrap/apps.py
+++ b/bootstrap/apps.py
@@ -1,8 +1,20 @@
 from django.apps import AppConfig
 
+
 class BootstrapConfig(AppConfig):
     name = 'bootstrap'
-    
+
     def get_bootstrap_widget(self):
         from bootstrap.widgets import BootstrapWidget
-        return BootstrapWidget
\ No newline at end of file
+        return BootstrapWidget
+
+    def get_bootstrap_field_templates(self, field, field_class, widget_class):
+        return [
+            'bootstrap/%s_%s.html' % (field.form.__class__.__name__.lower(), field.name),
+            'bootstrap/%s_%s.html' % (field_class, widget_class),
+            'bootstrap/%s.html' % field_class,
+            'bootstrap/field.html',
+        ]
+
+    def modify_bootstrap_field_classes(self, classes, field):
+        return classes
diff --git a/bootstrap/templatetags/bootstrap.py b/bootstrap/templatetags/bootstrap.py
index b997a1e..dd2f254 100644
--- a/bootstrap/templatetags/bootstrap.py
+++ b/bootstrap/templatetags/bootstrap.py
@@ -1,4 +1,5 @@
 from django import forms, template
+from django.apps import apps
 from django.conf import settings
 from django.core.paginator import Paginator
 from django.template import loader
@@ -13,6 +14,8 @@
 
 register = template.Library()
 
+bootstrap_app_config = apps.get_app_config("bootstrap")
+
 # https://fortawesome.github.io/Font-Awesome/icons/#file-type
 FONT_AWESOME_FILE_TYPE_ICON_MAP = {
     'doc': 'fa-file-word-o',
@@ -34,7 +37,7 @@ def bootstrap_icon(icon: str, **kwargs):
     """  
     Adds a bootstrap icon to the document. See https://icons.getbootstrap.com/ for more information. 
     Use kwargs to set the attributes of svg tag.  
-    
+
     :param icon: The name of the bootstrap icon you want. for example '0-circle'.  
     :param class: Use to add additional classes to the icon. Defaults to 'bi'.
     :param height: The height attribute of the icon. Defaults to '1em'.
@@ -42,7 +45,7 @@ def bootstrap_icon(icon: str, **kwargs):
     :param fill: The fill attribute of the icon. Defaults to 'currentColor'.
     """
     location= f'bootstrap/bootstrap-icons/bootstrap-icons.svg#{icon}'
-     
+
     return {'location': location,
             'attributes': { 
                 'class': 'bi',
@@ -105,18 +108,17 @@ def bootstrap_field(field, classes='', template=None, **kwargs):
         return ''
     field_class = field.field.__class__.__name__.lower()
     widget_class = field.field.widget.__class__.__name__.lower()
-    templates = [
-        'bootstrap/%s_%s.html' % (field.form.__class__.__name__.lower(), field.name),
-        'bootstrap/%s_%s.html' % (field_class, widget_class),
-        'bootstrap/%s.html' % field_class,
-        'bootstrap/field.html',
-    ]
+    templates = bootstrap_app_config.get_bootstrap_field_templates(
+        field=field,
+        field_class=field_class,
+        widget_class=widget_class,
+    )
     if template:
         templates.insert(0, template)
     extra_classes = getattr(field.field, 'css_classes', [])
     if extra_classes:
         classes += ' ' + ' '.join(extra_classes)
-
+    classes = bootstrap_app_config.modify_bootstrap_field_classes(classes=classes, field=field)
     use_fieldset = getattr(field.field.widget, 'use_fieldset', False)
     describedby = set(field.field.widget.attrs.get('aria-describedby', '').split())
     labelledby = set(field.field.widget.attrs.get('aria-labelledby', '').split())