You've probably already heard about Progressive Web Apps, but just to refresh, you are simply building an application from your website. If your application is PWA compatible, users should be able to add a shortcut (link) to the app to their home screen (desktop). The app should also work to some extent off-line, which is done with a help of the Service Worker. Note that by complying with PWA rules you will improve experience for all your users! Not just for mobile users.
In this article I will talk about some basics of transforming an existing website into a PWA. I'm saying those are the basics, but in fact, within a day or two you should be able to create a fully functional PWA. You need to avoid some traps on your way, but I'll try to guide you through this minefield.