> ## Documentation Index > Fetch the complete documentation index at: https://docs.flashduty.com/llms.txt > Use this file to discover all available pages before exploring further. # React Native SDK data collection > Learn about the event types, performance metrics, collection boundaries, and reporting behavior of the React Native RUM SDK This page describes what the React Native SDK collects, what is **outside its collection scope**, and how to control the scope. All events are written with `source: "react-native"`. ## Event types | Event | Trigger | Description | | --------- | ------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------- | | view | Recorded automatically by the navigation tracking package, or `DdRum.startView` / `stopView` | One screen visit; records the time spent, the number of actions / resources / errors inside it, and the performance metrics during the view | | action | `trackInteractions` collects `onPress` taps automatically, or `DdRum.addAction` | User interaction (tap / scroll / swipe / custom); can carry frustration signals | | resource | `trackResources` intercepts JS `XMLHttpRequest` / `fetch`, or `DdRum.startResource` / `stopResource` | One network request; records URL, method, status code, and duration | | error | Automatic (unhandled JS exception / native crash) or `DdRum.addError` | Errors and crashes, with type, message, and stack trace | | long task | Native main thread enabled by default (`nativeLongTaskThresholdMs`); JS thread requires `longTaskThresholdMs` | Thread blocking beyond the threshold | ## Automatically collected context Every event carries the following context (collected by the native layer): * **Application**: `service`, `version`, `env`, and `application.id` * **Device**: device model, OS and version, screen size * **Session**: `session.id`, sampled by `sessionSamplingRate` * **Connectivity**: network type (when available) * **User**: `usr.id` / `usr.name` / `usr.email` set through `DdSdkReactNative.setUser` * **Global attributes**: custom fields set through `DdSdkReactNative.setAttributes` ## Network request collection boundary Resource collection has a single entry point: the `XMLHttpRequest` proxy in the JavaScript layer (`fetch` in React Native is implemented on top of it). | Request origin | Collected | Recorded type | | ----------------------------------------------------------------------------------- | --------- | ----------------------------------------- | | `fetch` / `XMLHttpRequest` / axios and similar in application code | Yes | `xhr` | | Binary content such as images downloaded with `fetch` | Yes | `xhr` (not distinguished by Content-Type) | | Resources loaded by the native networking stack, such as `` | **No** | — | | Requests issued by native modules / third-party native SDKs themselves | **No** | — | As a result, the resource data of a React Native application contains API requests only, with no images, fonts, scripts, or other static resources. The console **does not show static-resource panels** for React Native applications. This is by design, following the collection boundary, and does not mean data is missing. ## Performance data The console shows a Performance page for React Native applications. Native vitals are collected by the wrapped Android / iOS SDKs, and the JS-thread frame rate is collected additionally by the React Native SDK: | Metric | Android | iOS | Description | | ------------------------ | --------- | ------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------- | | App launch time | Not yet | Cold / warm launch | Android does not report launch time yet; the corresponding console card shows "No data" | | Refresh rate | Supported | Supported | Rendering frame rate of the native UI thread | | **JS-thread frame rate** | Supported | Supported | React Native-specific; reflects whether application JS code is janky; shown on the console's Performance page | | CPU | Supported | Supported | CPU usage during the view | | Memory | Supported | Supported | Memory usage during the view | | Slow / frozen frames | Supported | Supported | Number of slow and frozen frames during the view | | ANR | Supported | — | Application not responding; whether non-fatal ANRs are collected by default depends on the Android version and can be overridden with `trackNonFatalAnrs` | | App Hang | — | Supported | Main-thread hang; requires `appHangThreshold`, disabled by default | The collection frequency of native vitals is controlled by `vitalsUpdateFrequency`, default `VitalsUpdateFrequency.AVERAGE`; set it to `NEVER` to disable. ## Logs `DdLogs.debug` / `info` / `warn` / `error` send log events, which are not RUM events. Currently **only Android actually sends them**; iOS is a no-op. ## Manual instrumentation Besides automatic collection, you can record events and attributes manually. ```typescript theme={null} import { DdRum, DdSdkReactNative, ErrorSource, RumActionType } from '@flashcatcloud/mobile-react-native'; // Manage views manually DdRum.startView('checkout', 'Checkout'); DdRum.stopView('checkout'); // Record an action manually DdRum.addAction(RumActionType.TAP, 'pay_button'); // Record a network request manually DdRum.startResource('req-1', 'GET', 'https://api.example.com/orders'); DdRum.stopResource('req-1', 200, 'xhr'); // Report an error manually DdRum.addError('payment failed', ErrorSource.SOURCE, stack); // Attach global attributes (written to all subsequent events) DdSdkReactNative.setAttributes({ tenant: 'acme' }); // Add a custom timing to the current view DdRum.addTiming('first_order_rendered'); ``` ## Sampling and controls | Option | Default | Description | | ------------------------------------------------------ | ------------------------------------ | ------------------------------------------------------------------------- | | `sessionSamplingRate` | 100 | Session sampling rate (percent); sessions not sampled produce no RUM data | | `resourceTracingSamplingRate` | 20 | Distributed tracing sampling rate on resources | | `telemetrySampleRate` | 20 | SDK internal telemetry sampling rate | | `trackInteractions` / `trackResources` / `trackErrors` | Constructor arguments, default false | Whether to collect actions / network requests / JS errors automatically | | `nativeCrashReportEnabled` | false | Whether to collect native crashes | | `trackFrustrations` | true | Whether to derive frustration signals from user actions | | `trackBackgroundEvents` | false | Whether to collect events while no view is active | | `vitalsUpdateFrequency` | `AVERAGE` | Collection frequency of native vitals; `NEVER` disables | | `nativeLongTaskThresholdMs` | 200 | Native main-thread long task threshold; `0` / `false` disables | | `longTaskThresholdMs` | 0 (disabled) | JS-thread long task threshold | | `trackNonFatalAnrs` | Platform default | Whether to collect non-fatal ANRs | | `appHangThreshold` | undefined | iOS App Hang threshold in seconds; unset means disabled | ## Data scrubbing Event mappers let you modify or drop data before it is reported, for scrubbing or noise filtering. See Advanced configuration. ```typescript theme={null} config.errorEventMapper = (event) => { // Return null to drop the event, or return a modified event if (event.message.includes('token=')) { return null; } return event; }; ``` ## Reporting behavior * The SDK buffers events in the native layer and uploads them in batches according to `uploadFrequency`, `batchSize`, and `batchProcessingLevel` * When the network is unavailable, events are persisted locally and retried once connectivity returns * The default intake endpoint is `https://browser.flashcat.cloud/api/v2/rum`; on-premises deployments can set the full RUM intake URL through `customEndpoints.rum` (it must include `/api/v2/rum` and keep the deployment's path prefix)