diff --git a/public/manifest.json b/public/manifest.json
index b3006bc..48b08d8 100644
--- a/public/manifest.json
+++ b/public/manifest.json
@@ -2,9 +2,11 @@
   "name": "Oikos Familienplaner",
   "short_name": "Oikos",
   "description": "Selbstgehosteter Familienplaner",
+  "id": "/",
   "start_url": "/",
   "scope": "/",
   "display": "standalone",
+  "display_override": ["standalone", "minimal-ui"],
   "orientation": "portrait-primary",
   "theme_color": "#007AFF",
   "background_color": "#F5F5F7",
diff --git a/public/sw.js b/public/sw.js
index fcce436..8efa454 100644
--- a/public/sw.js
+++ b/public/sw.js
@@ -12,9 +12,9 @@
  *   API: Immer Netzwerk (kein Caching von Nutzerdaten)
  */
 
-const SHELL_CACHE   = 'oikos-shell-v20';
-const PAGES_CACHE   = 'oikos-pages-v20';
-const ASSETS_CACHE  = 'oikos-assets-v20';
+const SHELL_CACHE   = 'oikos-shell-v21';
+const PAGES_CACHE   = 'oikos-pages-v21';
+const ASSETS_CACHE  = 'oikos-assets-v21';
 const ALL_CACHES    = [SHELL_CACHE, PAGES_CACHE, ASSETS_CACHE];
 
 // App-Shell: sofort benötigt für ersten Render
@@ -23,7 +23,10 @@ const APP_SHELL = [
   '/index.html',
   '/api.js',
   '/router.js',
+  '/i18n.js',
   '/rrule-ui.js',
+  '/locales/de.json',
+  '/locales/en.json',
   '/sw-register.js',
   '/lucide.min.js',
   '/styles/tokens.css',
diff --git a/server/index.js b/server/index.js
index 57b7356..eae7b25 100644
--- a/server/index.js
+++ b/server/index.js
@@ -112,6 +112,10 @@ app.use(express.static(path.join(__dirname, '..', 'public'), {
       // HTML, JS, CSS, JSON, manifest, sw — immer revalidieren
       res.setHeader('Cache-Control', 'no-cache, must-revalidate');
     }
+    // manifest.json: korrekter MIME-Type für PWA-Erkennung durch Chrome/Android
+    if (filePath.endsWith('manifest.json')) {
+      res.setHeader('Content-Type', 'application/manifest+json; charset=utf-8');
+    }
   },
 }));