My wife’s Japanese comic about our family is a responsive website.
A manifest turns a responsive website into an installable app. It lets users add it on their mobile phone’s home screen. When they launch the site it gets a splash screen and runs in full screen mode, basically behaving like a native app.
Caveat: For this to work HTTPS is required. Use certbot if you don’t already.
Now my family’s manga is an app. Horray for the open web!