I am developing a complex web app (it's free, with no ads and no registration). It works fine in Safari under iOS. The main difference with Chrome on Android is that when you go to the site, it will ask if you want to install the app. iOS is a little more opaque, you have to go to Share > Add to Home Screen to install on your phone. And it's also ambiguous as to whether a home screen icon is a web app or just a bookmark on iOS.
Safari on MacOS is more of an issue because it does not support web apps at all where Chrome, Edge, etc. have an option to install the site as a web app. You can accomplish the same things on my website without installing it as an app, however you will still see the browser interface whereas the web app runs full-screen without the browser interface. The less obvious difference is that web apps have persistent data storage but Safari websites do not. And MacOS has gotten more aggressive about automatically deleting site data if you don't visit often. IIRC, your data will be deleted after one week if you don't go to the site. A web app *should* store your data indefinitely on iOS, although Apple has made some confusing statements about this in the past. There is no persistent data storage in Safari on MacOS, since it doesn't support web apps.
Anyway, I decided to go the web app route because it's compatible with all platforms, a single web app works on Android, iOS, MacOS, Windows and Linux. And I also avoid having to pay registration fees, get my app approved etc. The downside is that web apps cannot directly access the filesystem on the device, for obvious security reasons. Files can only be saved to the downloads folder and the user must directly choose files to open (you can't open a file programatically, even if the app "knows" where it is located). For what I'm doing, this all works pretty well though.