How to add to the main screen devices Android ?

[EmmanuelMartinez]

How to add to the main screen devices Android ?
As you make your message add to home screen on mobile devices.
I study your code but I did not find the function can hopefully help me

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Como realizas el mensaje de agregar a pantalla principal en los dispositivos moviles.
Estudio tu código pero no encontré la función ojala me puedas ayudar

[RobertSmits]

Is build in to chrome.
The second time you open a PWA in chrome you get the banner to add to the home screen.

https://developers.google.com/web/fundamentals/engage-and-retain/app-install-banners/