Page 2 - React Native

Play Store policies are not only checked at submission, they are continuously reviewed against every published app through automated analysis. React Native apps often trip over the same stumbling blocks: undeclared sensitive permissions, a Data safety section that does not match reality, and an outdated target API level. This guide explains the most relevant policies and shows how to avoid rejections and account suspensions.

The JavaScript Interface, JSI, connects the JavaScript runtime and native C++ code directly, without JSON serialization or an asynchronous bridge round trip. Building a HostObject shows how synchronous native bindings work in practice, why the performance gain matters mainly for frequent calls, and where the limits of this approach lie.

Expo Router replaces manually wired navigators with the app/ directory as the single source of truth. Nested layouts via _layout.tsx, dynamic segments like [id].tsx, route groups with parentheses, and deep linking that works automatically make React Native navigation predictable and type safe.

Teams that build mobile apps without an offline-first architecture lose users at every dead zone. WatermelonDB combines a SQLite foundation, lazy loading and reactive observables with a built-in sync engine, so React Native apps respond instantly on the device while reliably synchronizing with the server in the background.

EAS Build compiles React Native and Expo apps in the cloud into installable iOS and Android binaries, manages certificates, provisioning profiles, and keystores automatically, and makes builds reproducible through eas.json. This guide explains build profiles, environment variables, config plugins for native modules, and the path from build to submission with eas submit.

React Native does not render on the Apple Watch or a Wear OS watch, watch apps are always standalone native targets. This article covers the communication strategy through WatchConnectivity and the Wearable Data Layer API, plus the realistic limits of code reuse.

Custom URL schemes can be claimed by any app on the device, which opens the door to hijacking. iOS Universal Links and Android App Links solve this with a cryptographically verified domain, but they demand correct configuration on both the server and the app side. This article walks through setting up React Native deep linking properly, wiring it into React Navigation, and testing it reliably.

A React Native design system bundles design tokens, proven components and theming into one versioned package, so teams stop rebuilding buttons, cards and forms from scratch for every new app. This article shows how a real component library grows from the first tokens into a reusable npm package.

AsyncStorage stores values unencrypted as plain text, readable with physical access or on a rooted device. Secure storage via the iOS Keychain and Android Keystore encrypts secrets at the operating system level and can additionally bind them to biometry. This article shows how react-native-keychain and expo-secure-store correctly store access tokens, refresh tokens, and other sensitive data.

Anyone who has tested a React Native app with Appium or a Selenium-based tool knows the problem: sleeps, flaky assertions, tests that pass locally and fail in CI. Detox solves exactly that with a gray-box approach that synchronizes with the app's event loop instead of waiting blindly.