Web apps do not take up storage space on your phone. No running background. Making mobile work slowly. And not updating itself. Do not use your personal information. Web apps are designed to save bandwidth. You can also use the internet at low speeds.
Add Web App on home screen. Iphone and Android.
For Chrome browser into a Web page to add. And for all the top-right corner and select Add to Home Screen.
Safari Browser for a page to add. The middle and bottom menu and select Add to Home screen.