How is a home screen app icon different from a tab in your browser, if it leads to what is essentially a web app? I count such apps as a success wrt "betting on

How is a home screen app icon different from a tab in your browser, if it leads to what is essentially a web app? I count such apps as a success wrt "betting on the web". Sadly, the capabilities of PWAs are very much second class on every mobile platform right now. But I don't think it will stay that way forever.