「アプリをインストール」するだけのPWA

manifest.json

{
	"name": "{アプリケーション名}",
	"display": "standalone",
	"start_url": "index.html",
	"orientation": "portrait",
	"icons": [
		{
			"src": "images/logo.png",
			"sizes": "192x192"
		}
	]
}

sw.js

self.addEventListener('install', event => event.waitUntil());
self.addEventListener('fetch', event => event.respondWith());

if (navigator.serviceWorker) {
    navigator.serviceWorker.register('sw.js');
}