If you wanna use the web technologies (HTML/JS/CSS, Angular, React, Vue, Svelte...) you can use ionic/capacitor capacitorjs.com/
If you wanna have all native access but write code once (so not for android and iOS two different apps). You can use Flutter, Dart, React Native or Nativescript
You can also make a Progressive Web App. Benefits of PWA's: they are fast, small sized (4 ~ 10 KB) and use the simple well known web techniques.
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Lots of possibilities: