TL;DR

For a React web app that people use on phones and desktops, Wingo UI does the most for you: its selects, popovers, menus and dialogs open as draggable bottom sheets below 768px and its buttons grow to 44px on touch. For a mobile-only app or a Capacitor build with a native iOS or Material look, Ionic React is the stronger pick, with Framework7 and antd-mobile as alternatives. MUI, shadcn/ui, HeroUI and Mantine render fine on a 390px screen but leave most phone behavior, from sheets to safe areas, to you.

Picking the best React component library for mobile comes down to what each component does on a phone. This comparison is for React web apps: a Next.js app that people open in a phone browser, add to the home screen or ship inside Capacitor. React Native kits are out of scope. Four things decide the choice: what a select or menu opens on a 390px screen, how big the targets are under a thumb, whether fixed bars clear the notch and the home indicator, and which gestures work.…