Demonstration of a neat trick using current architecture and implementations
of Progressive Web Applications backbone (Web App Manifest). Tested on
Android/Chrome&Firefox:
In settings pick "add to Homescreen" for Chrome or in Firefox
click the home icon in the URL bar (unless current page
asked you to install the app; try refreshing the page
several times?
On your smartphone, switch to the app added to your homescreen.
The app explains the rest.
Installed the app already
(if nothing happens install it manually from preferences - "add to Homescreen"