Implement all best practices for web app manifest

src/manifest.json

@@ -1,21 +1,37 @@
 {
   "name": "Apple Music",
   "short_name": "Apple Music",
+  "description": "Apple Music PWA",
+  "lang": "en",
+  "categories": ["music"],
   "theme_color": "#1e3264",
   "background_color": "#212121",
-  "display": "browser",
-  "scope": "/",
-  "start_url": "/",
+  "display": "standalone",
+  "scope": "./",
+  "start_url": "./?utm_source=web_app_manifest",
   "icons": [
     {
-      "src": "/assets/icons/android-chrome-192x192.png",
+      "src": "./assets/icons/android-chrome-192x192.png",
       "sizes": "192x192",
       "type": "image/png"
     },
     {
-      "src": "/assets/icons/android-chrome-512x512.png",
+      "src": "./assets/icons/android-chrome-512x512.png",
       "sizes": "512x512",
       "type": "image/png"
     }
+  ],
+  "screenshots": [],
+  "prefer_related_applications": false,
+  "related_applications": [
+    {
+      "platform": "play",
+      "id": "com.apple.android.music",
+      "url": "https://play.google.com/store/apps/details?id=com.apple.android.music&referrer=utm_source%3Dweb_app_manifest"
+    },
+    {
+      "platform": "itunes",
+      "url": "https://itunes.apple.com/app/id1108187390"
+    }
   ]
-}
+}