I was wondering what's the solution of progressive web app for IOS devices since their default brower SAFARI doesn't yet support progressive web apps. Whats the alternate then for IOS counterparts?
Please mind that "Browsers that support Progressive Web Apps" is not a real term, PWA itself is a set of features that a web app can provide for users. So it's not just only about Service Worker and App Manifest.
Check out: Baseline PWA Checklist.
Here are what you can do to achieve PWA on iOS/Safari at the moment this answer is created:
As you can see, almost everything is working, even if your page can't work offline on iOS/Safari, there is still a huge benefit of "upgrading" your web app into a PWA.
What you really want is not the fancy title of "Progressive Web Apps" but a good web app that delivers a good experience and features for users. This is a journey as you can accomplish it by each small part, that's why it is called "Progressive".
Note on the "Add to Home screen: Safari has its own spec for "Home screen icon" called apple-mobile-web-app-capable
in the meta tags. Web App Manifest Generator has a fallback for iOS using this meta tags.