The same codebase should include ios, android and a backend. The mobile app need to be publishable to the app stores, therefore a webview-only app is not allowed.
Close winners: React,flutter,ionic,nativescript: 1 codebase for ios/android + 1 codebase for a json web api = 2 codebases
I heard about hotwire.dev that promise to do that with strada, however I know nothing about how this will work.