Comment by systoll

Android is in basically the same situation.

Obviously both Android & iOS let you open things in the default browser.

iOS has SFSafariViewController, which more-or-less corresponds to Chrome Custom Tabs on Android. These basically make a browser UI that is in the of the app for the purposes of multitasking/app-switching, but which is controlled by the browser. Devs can't inject code into these.

And both have WebViews, which let the dev do more-or-less whatever they want inside their own app.