Installing the app on your phone
The app can be installed on a phone so it behaves like a native app, with its own icon and push notifications. You don't need to find it in an app store. You install it from the browser after signing in.
On iPhone, open the app in Safari, tap the Share button, and choose Add to Home Screen. On Android, open it in Chrome and choose Install app or Add to Home Screen from the menu.
Push notifications need to be allowed once, the first time you're asked.