diff --git a/src/pyj/read_book/viewport.pyj b/src/pyj/read_book/viewport.pyj
index c2db19f19f..d4d73d4452 100644
--- a/src/pyj/read_book/viewport.pyj
+++ b/src/pyj/read_book/viewport.pyj
@@ -5,7 +5,7 @@ from __python__ import bound_methods, hash_literals
 FUNCTIONS = 'x y scroll_to scroll_into_view reset_globals __reset_transforms window_scroll_pos content_size'.split(' ')
 
 from read_book.globals import get_boss, viewport_mode_changer
-from utils import document_height, document_width, is_ios
+from utils import document_height, document_width, ios_major_version
 
 class ScrollViewport:
 
@@ -321,7 +321,7 @@ class IOSScrollViewport(ScrollViewport):
         self.__reset_transforms()
 
 
-if is_ios:
+if 1 < ios_major_version < 15:
     scroll_viewport = IOSScrollViewport()
 else:
     scroll_viewport = ScrollViewport()
diff --git a/src/pyj/utils.pyj b/src/pyj/utils.pyj
index 362c9aa3ab..df5a9dc74c 100644
--- a/src/pyj/utils.pyj
+++ b/src/pyj/utils.pyj
@@ -8,9 +8,14 @@ from book_list.theme import get_font_family
 
 
 is_ios = v'!!navigator.platform && /iPad|iPhone|iPod/.test(navigator.platform)'
+ios_major_version = 0
 if !is_ios and v'!!navigator.platform' and window? and window.navigator.platform is 'MacIntel' and window.navigator.maxTouchPoints > 1:
     # iPad Safari in desktop mode https://stackoverflow.com/questions/57765958/how-to-detect-ipad-and-ipad-os-version-in-ios-13-and-up
     is_ios = True
+if is_ios:
+    v = v'navigator.appVersion.match(/OS (\d+)/)'
+    if v and v[1]:
+        ios_major_version = parseInt(v[1], 10) or 0
 
 
 def default_context_menu_should_be_allowed(evt):