You may be looking for the “Add to Homescreen” feature as used on Android and iOS, though it is only supported in some browsers. This feature allows a user to open a web app in a quasi-full-screen mode which hides browser-like appearances (sometimes call ‘browser chrome’).
For iOS, see:
Be aware that this feature only works with the built in iOS Safari browser. Chrome for iOS is not supported.
For Android, see:
Supported in Chrome for Android, but Firefox for Android support may be coming.
In AppStudio 5, there was full support for Android’s Add to Homescreen feature, but it was removed in version 6 (though some traces of it remain). You can still roll your own manifest.json file and add the needed tags to the extraheaders property on your own, but it’s more work now than it used to be.