Visitors to your website on mobile devices should be prompted with options to install the app and receive notifications.
Each mobile device and browser handles the installation of PWAs differently as this is a new technology without standardization.
Unfortunately, Apple has been slow in rolling out support for PWAs and Web Push Notifications. The PWAs need to be installed manually from the Safari browser menu. Apple supports web push notification on Safari on their desktop but not yet on iOS. Once they do support it, we will as well.