Creating functional PWA for iOS is tough and requires a lot of workarounds, but it is possible - as you may have seen in my previous article - Few Tips That Will Make Your PWA on iOS Feel Like Native. I wrote that article a few months ago, but unfortunately, it is not outdated yet - support for PWA on iOS is still really poor.
I recently had the opportunity to work on a fantastic research and development project at Netguru. The goal of the project (codename "Wordguru") was to create a card game that anyone can play with their friends. You can check the outcome here.