diff --git a/packages/frontend/component/src/components/app-sidebar/index.jotai.ts b/packages/frontend/component/src/components/app-sidebar/index.jotai.ts
index 696e8620f..f645cc33f 100644
--- a/packages/frontend/component/src/components/app-sidebar/index.jotai.ts
+++ b/packages/frontend/component/src/components/app-sidebar/index.jotai.ts
@@ -2,8 +2,10 @@ import { atom } from 'jotai';
 import { atomWithStorage } from 'jotai/utils';
 
 export const APP_SIDEBAR_OPEN = 'app-sidebar-open';
-export const appSidebarOpenAtom = atomWithStorage(APP_SIDEBAR_OPEN, true);
-export const appSidebarFloatingAtom = atom(false);
+export const isMobile = window.innerWidth < 768;
+
+export const appSidebarOpenAtom = atomWithStorage(APP_SIDEBAR_OPEN, !isMobile);
+export const appSidebarFloatingAtom = atom(isMobile);
 
 export const appSidebarResizingAtom = atom(false);
 export const appSidebarWidthAtom = atomWithStorage(