react-native-expert

Replace FlatList with LegendList or FlashList, which virtualize rendering so only visible items mount. Keep list items lightweight by passing pre-computed primitives as props, avoid inline objects in renderItem, and never use ScrollView with .map() for dynamic lists.

Use NativeTabs from expo-router/unstable-native-tabs in your tab group's _layout.tsx file, available in Expo SDK 53+. Define NativeTabs.Trigger entries with Label and icon props using SF Symbols on iOS and Material icons on Android.

React Native crashes when a falsy value like 0 or an empty string renders outside a Text component via the && operator. Use a ternary returning null, boolean coercion with !!, or an early return instead.

Zustand works best for a single store with persistence via its persist middleware combined with MMKV. Jotai suits fine-grained atomic state with derived atoms, and both avoid the re-render problems React Context causes in list items.

Animating layout properties like width, height, margin, or padding triggers layout recalculation every frame and causes jank. Animate only transform and opacity, which run on the GPU, and derive visuals from state shared values using interpolate.

Use expo-secure-store for tokens, passwords, and credentials since it encrypts data with the device keychain or keystore. Use MMKV for fast synchronous general-purpose storage and avoid AsyncStorage for new projects.