Chapter 199 · Omnibus Instrument Product Analytics
Subchapter 199.50
references/react-native.mdMarkdown44 KBView on GitHub
Our React Native enables you to integrate PostHog with your React Native project. For React Native projects built with Expo, there are no mobile native dependencies outside of supported Expo packages.
To install, add the posthog-react-native package to your project as well as the required peer dependencies.
Terminal
PostHog AI
npx expo install posthog-react-native expo-file-system expo-application expo-device expo-localizationTerminal
PostHog AI
yarn add posthog-react-native @react-native-async-storage/async-storage react-native-device-info react-native-localize
# or
npm i -s posthog-react-native @react-native-async-storage/async-storage react-native-device-info react-native-localizeIf you’re using React Native Web (opens in a new tab) or React Native macOS (opens in a new tab), do not use the expo-file-system (opens in a new tab) package since the Web and macOS targets aren’t supported, use the @react-native-async-storage/async-storage (opens in a new tab) package instead.
The recommended way to set up PostHog for React Native is to use the PostHogProvider. This utilizes the Context API to pass the PostHog client around, and enables autocapture (opens in a new tab).
To set up PostHogProvider, add it to your App.js or App.ts file:
App.js
PostHog AI
// App.(js|ts)
import { usePostHog, PostHogProvider } from 'posthog-react-native'
...
export function MyApp() {
return (
<PostHogProvider apiKey="<ph_project_token>" options={{
// usually 'https://us.i.posthog.com' or 'https://eu.i.posthog.com'
host: 'https://us.i.posthog.com',
}}>
<MyComponent />
</PostHogProvider>
)
}Then you can access PostHog using the usePostHog() hook:
React Native
PostHog AI
const MyComponent = () => {
const posthog = usePostHog()
useEffect(() => {
posthog.capture("event_name")
}, [posthog])
}If you prefer not to use the provider, you can initialize PostHog in its own file and import the instance from there:
posthog.ts
PostHog AI
import PostHog from 'posthog-react-native'
export const posthog = new PostHog('<ph_project_token>', {
// usually 'https://us.i.posthog.com' or 'https://eu.i.posthog.com'
host: 'https://us.i.posthog.com'
})Then you can access PostHog by importing your instance:
React Native
PostHog AI
import { posthog } from './posthog'
export function MyApp1() {
useEffect(() => {
posthog.capture('event_name')
}, [])
return <View>Your app code</View>
}You can even use this instance with the PostHogProvider:
React Native
PostHog AI
import { posthog } from './posthog'
export function MyApp() {
return <PostHogProvider client={posthog}>{/* Your app code */}</PostHogProvider>
}Set up a reverse proxy (recommended)
We recommend setting up a reverse proxy (opens in a new tab), so that events are less likely to be intercepted by tracking blockers.
We have our own managed reverse proxy service (opens in a new tab), which is free for all PostHog Cloud users, routes through our infrastructure, and makes setting up your proxy easy.
If you don’t want to use our managed service then there are several other options for creating a reverse proxy, including using Cloudflare (opens in a new tab), AWS Cloudfront (opens in a new tab), and Vercel (opens in a new tab).
Grouping products in one project (recommended)
If you have multiple customer-facing products (e.g. a marketing website + mobile app + web app), it’s best to install PostHog on them all and group them in one project (opens in a new tab).
This makes it possible to track users across their entire journey (e.g. from visiting your marketing website to signing up for your product), or how they use your product across multiple platforms.
Add IPs to Firewall/WAF allowlists (recommended)
For certain features like heatmaps (opens in a new tab), your Web Application Firewall (WAF) may be blocking PostHog’s requests to your site. Add these IP addresses to your WAF allowlist or rules to let PostHog access your site.
EU: 3.75.65.221, 18.197.246.42, 3.120.223.253
US: 44.205.89.55, 52.4.194.122, 44.208.188.173
These are public, stable IPs used by PostHog services (e.g., Celery tasks for snapshots).
You can further customize how PostHog works through its configuration on initialization.
| Attribute | Description |
|---|---|
| hostType: StringDefault: https://us.i.posthog.com (opens in a new tab) | PostHog API host (usually https://us.i.posthog.com (opens in a new tab) by default or https://eu.i.posthog.com (opens in a new tab)). Host is optional if you use https://us.i.posthog.com (opens in a new tab). |
| flushAtType: NumberDefault: 20 | The number of events to queue before sending to PostHog (flushing). |
| flushIntervalType: NumberDefault: 10000 | The interval in milliseconds between periodic flushes. |
| maxBatchSizeType: NumberDefault: 100 | The maximum number of queued messages to be flushed as part of a single batch (must be higher than flushAt). |
| maxQueueSizeType: NumberDefault: 1000 | The maximum number of cached messages either in memory or on the local storage (must be higher than flushAt). |
| disabledType: BooleanDefault: false | If set to true, the SDK is essentially disabled (useful for local environments where you don’t want to track anything). |
| defaultOptInType: BooleanDefault: true | If set to false, the SDK will not track until the optIn() function is called. |
| sendFeatureFlagEventType: BooleanDefault: true | Whether to track that getFeatureFlag was called (used by experiments). |
| preloadFeatureFlagsType: BooleanDefault: true | Whether to load feature flags when initialized or not. |
| bootstrapType: ObjectDefault: {} | An object containing the distinctId, isIdentifiedId, featureFlags, and featureFlagPayloads keys. distinctId is a string, and featureFlags and featureFlagPayloads are objects of key-value pairs. Used to ensure data is available as soon as the SDK loads. |
| fetchRetryCountType: NumberDefault: 3 | How many times HTTP requests will be retried. |
| fetchRetryDelayType: NumberDefault: 3000 | The delay between HTTP request retries. |
| requestTimeoutType: NumberDefault: 10000 | Timeout in milliseconds for any calls. |
| featureFlagsRequestTimeoutMsType: NumberDefault: 10000 | Timeout in milliseconds for feature flag calls. |
| sessionExpirationTimeSecondsType: NumberDefault: 1800 | For session analysis, how long before a session expires (defaults to 30 minutes). |
| persistenceType: StringDefault: file | Allows you to provide the storage type. file will try to load the best available storage, the provided customStorage, customAsyncStorage, or in-memory storage. |
| customAppPropertiesType: Object or FunctionDefault: null | Allows you to provide your own implementation of the common information about your App or a function to modify the default App properties generated. |
| customStorageType: ObjectDefault: null | Allows you to provide a custom asynchronous storage such as async-storage, expo-file-system, or a synchronous storage such as mmkv. If not provided, PostHog will attempt to use the best available storage via optional peer dependencies. If persistence is set to memory, this option is ignored. |
| captureAppLifecycleEventsType: BooleanDefault: false | Captures app lifecycle events such as Application Installed, Application Updated, Application Opened, Application Became Active, and Application Backgrounded. By default, this is false. |
| disableGeoipType: BooleanDefault: false | When true, disables automatic GeoIP resolution for events and feature flags. |
| enableSessionReplayType: BooleanDefault: false | Enable Recording of Session replay for Android and iOS. |
| sessionReplayConfigType: ObjectDefault: null | Session replay configuration. See the replay install docs (opens in a new tab) for more details. |
| enablePersistSessionIdAcrossRestartType: BooleanDefault: false | When true, persists the $session_id across app restarts. If false, $session_id always resets on app restart. |
| evaluationContextsType: Array of StringsDefault: undefined | Evaluation context tags that constrain which feature flags are evaluated. When set, only flags with matching evaluation context tags (or no evaluation context tags) will be returned. This helps reduce unnecessary flag evaluations and improves performance. See evaluation contexts documentation (opens in a new tab) for more details. Available in version 4.8.0+. The legacy parameter evaluationEnvironments (version 4.7.2+) is also supported for backward compatibility. |
| before_sendType: FunctionDefault: undefined | A callback function that is called before each event is sent to PostHog. You can use it to modify, filter, or suppress events. Return null to drop the event, or return the modified event to send it. See customizing exception capture for details. |
You can send custom events using capture:
React Native
PostHog AI
posthog.capture('user_signed_up')Tip: We recommend using a
[object] [verb]format for your event names, where[object]is the entity that the behavior relates to, and[verb]is the behavior itself. For example,project created,user signed up, orinvite sent.
Optionally, you can include additional information with the event by including a properties (opens in a new tab) object:
React Native
PostHog AI
posthog.capture('user_signed_up', {
login_type: "email",
is_free_trial: true
})When using @react-navigation/native (opens in a new tab) v6 or lower, screen tracking is automatically captured if the autocapture (opens in a new tab) property is used in the PostHogProvider:
It is important that the PostHogProvider is configured as a child of the NavigationContainer:
React Native
PostHog AI
// App.(js|ts)
import { PostHogProvider } from 'posthog-react-native'
import { NavigationContainer } from '@react-navigation/native'
export function App() {
return (
<NavigationContainer>
<PostHogProvider apiKey="<ph_project_token>" autocapture>
{/* Rest of app */}
</PostHogProvider>
</NavigationContainer>
)
}When using @react-navigation/native (opens in a new tab) v7 or higher, screen tracking has to be manually captured:
React Native
PostHog AI
// App.(js|ts)
import { PostHogProvider } from 'posthog-react-native'
import { NavigationContainer } from '@react-navigation/native'
// Using `PostHogProvider` is optional, but needed if you want to capture touch events automatically with the `captureTouches` option.
export function App() {
return (
<NavigationContainer>
<PostHogProvider apiKey="<ph_project_token>" autocapture={{
captureScreens: false, // Screen events are handled differently for v7 and higher
captureTouches: true,
}}>
{/* Rest of app */}
</PostHogProvider>
</NavigationContainer>
)
}Check out and set it up the official way for Screen tracking for analytics (opens in a new tab).
Then call the screen method within the trackScreenView method.
React Native
PostHog AI
const posthog = usePostHog() // use the usePostHog hook if using the PostHogProvider or your own custom posthog instance
// you can read the params from `getCurrentRoute()`
posthog.screen(currentRouteName, params)First, simplify the wrapping of your screens with a shared PostHogProvider:
React Native
PostHog AI
import PostHog, { PostHogProvider } from 'posthog-react-native'
import { Navigation } from 'react-native-navigation';
export const posthog = new PostHog('<ph_project_token>');
export const SharedPostHogProvider = (props: any) => {
return (
<PostHogProvider client={posthog} autocapture={{
captureScreens: false, // Screen events are handled differently for react-native-navigation
captureTouches: true,
}}>
{props.children}
</PostHogProvider>
);
};Then, every screen needs to be wrapped with this provider if you want to capture touches or use the usePostHog() hook
React Native
PostHog AI
export const MyScreen = () => {
return (
<SharedPostHogProvider>
<View>
...
</View>
</SharedPostHogProvider>
);
};
Navigation.registerComponent('Screen', () => MyScreen);
Navigation.events().registerAppLaunchedListener(async () => {
posthog.initReactNativeNavigation({
navigation: {
// (Optional) Set the name based on the route. Defaults to the route name.
routeToName: (name, properties) => name,
// (Optional) Tracks all passProps as properties. Defaults to undefined
routeToProperties: (name, properties) => properties,
},
captureScreens: true,
});
});Check out and set it up the official way for Screen tracking for analytics (opens in a new tab).
Then call the screen method within the useEffect callback.
React Native
PostHog AI
const posthog = usePostHog() // use the usePostHog hook if using the PostHogProvider or your own custom posthog instance
posthog.screen(pathname, params)If you prefer not to use autocapture, you can manually capture screen views by calling posthog.screen(). This function requires a name. You may also pass in an optional properties object.
JavaScript
PostHog AI
posthog.screen('dashboard', {
background: 'blue',
hero: 'superhog',
})PostHog autocapture can automatically track the following events for you:
@react-navigation/native (v6 or lower) or react-native-navigation), check out the capturing screen views (opens in a new tab) section⚠️ React Navigation v7 users
React Navigation v7 restricts navigation hooks (such as
useNavigationState) to components rendered inside a Screen that belongs to a Navigator.Because of this change, automatic screen tracking may throw errors if PostHog is initialized outside a screen context. This commonly affects apps upgrading from React Navigation v6 to v7.
For React Navigation v7, we recommend disabling automatic screen capture for screens and manually calling
posthog.screen()inside each screen component. See the Capturing screen views (opens in a new tab) section below.
With autocapture, all touch events for children of PosthogProvider are tracked, capturing a snapshot of the view hierarchy at that point. This enables you to create insights (opens in a new tab) in PostHog without having to add custom events.
PostHog will try to generate a sensible name for the touched element based on the React component displayName or name. If you prefer, you can set your own name using the ph-label prop:
React Native
PostHog AI
<View ph-label="my-special-label"></View>React Native
PostHog AI
<PostHogProvider apiKey="<ph_project_token>" autocapture={{
captureTouches: true,
captureScreens: true,
ignoreLabels: [], // Any labels here will be ignored from the stack in touch events
customLabelProp: "ph-label",
maxElementsCaptured: 20,
noCaptureProp: "ph-no-capture",
propsToCapture: ["testID"], // Limit which props are captured. By default, identifiers and text content are captured.
navigation: {
// By default, only the screen name is tracked but it is possible to track the
// params or modify the name by intercepting the autocapture like so
routeToName: (name, params) => {
if (params.id) return `${name}/${params.id}`
return name
},
routeToProperties: (name, params) => {
if (name === "SensitiveScreen") return undefined
return params
},
},
}}>
...
</PostHogProvider>If there are elements you don’t want to be captured, you can add the ph-no-capture property. If this property is found anywhere in the view hierarchy, the entire touch event is ignored:
React Native
PostHog AI
<View ph-no-capture>Sensitive view here</View>We highly recommend reading our section on Identifying users (opens in a new tab) to better understand how to correctly use this method.
Using identify, you can associate events with specific users. This enables you to gain full insights as to how they’re using your product across different sessions, devices, and platforms.
An identify call has the following arguments:
React Native
PostHog AI
posthog.identify('distinctID',
{ // ($set):
email: 'user@posthog.com',
name: 'My Name'
}
)$set_once works just like $set, except that it will only set the property if the user doesn’t already have that property set. See the difference between $set and $set_once (opens in a new tab)
React Native
PostHog AI
posthog.identify('distinctID',
{
$set: {
email: 'user@posthog.com',
name: 'My Name'
},
$set_once: {
date_of_first_log_in: '2024-03-01'
}
}
)You should call identify as soon as you’re able to. Typically, this is after your user logs in. This ensures that events sent during your user’s sessions are correctly associated with them.
When you call identify, all previously tracked anonymous events (opens in a new tab) will be linked to the user.
You may find it helpful to get the current user’s distinct ID. For example, to check whether you’ve already called identify for a user or not.
To do this, call posthog.get_distinct_id(). This returns either the ID automatically generated by PostHog or the ID that has been passed by a call to identify().
Sometimes, you want to assign multiple distinct IDs to a single user. This is helpful when your primary distinct ID is inaccessible. For example, if a distinct ID used on the frontend is not available in your backend.
In this case, you can use alias to assign another distinct ID to the same user.
React Native
PostHog AI
// Sets alias for current user
posthog.alias('distinct_id')We strongly recommend reading our docs on alias (opens in a new tab) to best understand how to correctly use this method.
Person properties enable you to capture, manage, and analyze specific data about a user. You can use them to create filters (opens in a new tab) or cohorts (opens in a new tab), which can then be used in insights (opens in a new tab), feature flags (opens in a new tab), and more.
To set a user’s properties, include the $set or $set_once property when capturing any event:
JavaScript
PostHog AI
posthog.capture('some_event', { $set: { userProperty: 'value' } })$set_once works just like $set, except it only sets the property if the user doesn’t already have that property set.
JavaScript
PostHog AI
posthog.capture('some_event', { $set_once: { userProperty: 'value' } })Super properties are properties associated with events that are set once and then sent with every capture call, be it a $screen, an autocaptured touch, or anything else.
They are set using posthog.register, which takes a properties object as a parameter, and they persist across sessions.
For example:
JavaScript
PostHog AI
posthog.register({
'icecream pref': 'vanilla',
team_id: 22,
})The call above ensures that every event sent by the user will include "icecream pref": "vanilla" and "team_id": 22. This way, if you filtered events by property using icecream_pref = vanilla, it would display all events captured on that user after the posthog.register call, since they all include the specified Super Property.
This does not set the user’s properties. This only sets the properties for their events. To store person properties, see the setting person properties section.
Super Properties are persisted across sessions so you have to explicitly remove them if they are no longer relevant. In order to stop sending a Super Property with events, you can use posthog.unregister, like so:
JavaScript
PostHog AI
posthog.unregister('icecream pref'),This will remove the super property and subsequent events will not include it.
If you are doing this as part of a user logging out you can instead simply posthog.reset() which takes care of clearing all stored Super Properties and more.
You can completely opt-out users from data capture. To do this, there are two options:
opt_out_capturing_by_default to true in your PostHog config:JavaScript
PostHog AI
posthog.init('<ph_project_token>', {
opt_out_capturing_by_default: true,
});opt_out_capturing():JavaScript
PostHog AI
posthog.opt_out_capturing()Similarly, you can opt users in:
JavaScript
PostHog AI
posthog.opt_in_capturing()To check if a user is opted out:
JavaScript
PostHog AI
posthog.has_opted_out_capturing()You can set the number of events in the configuration that should queue before flushing. Setting this to 1 will send events immediately and will use more battery. This is set to 20 by default.
You can also configure the flush interval. By default we flush all events after 30 seconds, no matter how many events have gathered.
You can also manually flush the queue. If a flush is already in progress it returns a promise for the existing flush.
JavaScript
PostHog AI
await posthog.flush()To reset the user’s ID and anonymous ID, call reset. Usually you would do this right after the user logs out.
JavaScript
PostHog AI
posthog.reset()The PostHog React Native SDK will continue to capture events when the device is offline. When persistence is set to file (by default), the events are stored in a queue in the device’s file storage. Even when the app is closed, the events are persisted and will be flushed when the app is opened again.
maxQueueSize in the configuration.By default, PostHog has tracking enabled unless it is forcefully disabled by default using the option { defaultOptIn: false }.
You can give your users the option to opt in or out by calling the relevant methods. Once these have been called they are persisted and will be respected until optIn/Out is called again or the reset function is called.
To opt in/out of tracking, use the following calls.
JavaScript
PostHog AI
posthog.optedOut // See if a user has opted out
posthog.optIn() // opt in
posthog.optOut() // opt outIf you still wish capture these events but want to create a distinction between users and team in PostHog, you should look into Cohorts (opens in a new tab).
PostHog’s feature flags (opens in a new tab) enable you to safely deploy and roll back new features as well as target specific users and groups with them.
There are two ways to implement feature flags in React Native:
React Native
PostHog AI
import { useFeatureFlag } from 'posthog-react-native'
const MyComponent = () => {
const booleanFlag = useFeatureFlag('key-for-your-boolean-flag')
if (booleanFlag === undefined) {
// the response is undefined if the flags are being loaded
return null
}
// Optional use the 'useFeatureFlagWithPayload' hook for fetching the feature flag payload
return booleanFlag ? <Text>Testing feature 😄</Text> : <Text>Not Testing feature 😢</Text>
}React Native
PostHog AI
import { useFeatureFlag } from 'posthog-react-native'
const MyComponent = () => {
const multiVariantFeature = useFeatureFlag('key-for-your-multivariate-flag')
if (multiVariantFeature === undefined) {
// the response is undefined if the flags are being loaded
return null
} else if (multiVariantFeature === 'variant-name') { // replace 'variant-name' with the name of your variant
// Do something
}
// Optional use the 'useFeatureFlagWithPayload' hook for fetching the feature flag payload
return <div/>
}React Native
PostHog AI
// Defaults to undefined if not loaded yet or if there was a problem loading
posthog.isFeatureEnabled('key-for-your-boolean-flag')
// Defaults to undefined if not loaded yet or if there was a problem loading
posthog.getFeatureFlag('key-for-your-boolean-flag')
// Multivariant feature flags are returned as a string
posthog.getFeatureFlag('key-for-your-multivariate-flag')
// Optional fetch the payload returns 'JsonType' or undefined if not loaded yet or if there was a problem loading
posthog.getFeatureFlagPayload('key-for-your-multivariate-flag')Every time a user opens the app, we send a request in the background to fetch the feature flags that apply to that user. We store those flags in the storage.
This means that for most screens, the feature flags are available immediately — except for the first time a user visits.
To handle this, you can use the onFeatureFlags callback to wait for the feature flag request to finish:
React Native
PostHog AI
posthog.onFeatureFlags((flags) => {
// feature flags are guaranteed to be available at this point
if (posthog.isFeatureEnabled('flag-key')) {
// do something
}
})PostHog loads feature flags when instantiated and refreshes whenever methods are called that affect the flag.
If want to manually trigger a refresh, you can call reloadFeatureFlagsAsync():
React Native
PostHog AI
posthog.reloadFeatureFlagsAsync().then((refreshedFlags) => console.log(refreshedFlags))Or when you want to trigger the reload, but don’t care about the result:
React Native
PostHog AI
posthog.reloadFeatureFlags()The React Native SDK caches feature flag values in AsyncStorage. Cached values persist indefinitely with no TTL until updated by a successful API call. This enables offline support and reduces latency, but means inactive users may see stale flag values from their last session.
For example, if a user last opened your app when a flag was false, that value remains cached even after you roll it out to 100%. When they reopen the app, the SDK returns the cached false first, then fetches the fresh true value from the API.
To ensure fresh flag values:
React Native
PostHog AI
// Force refresh on app start
await posthog.reloadFeatureFlagsAsync()Or clear cached values for inactive users:
React Native
PostHog AI
if (lastActiveDate < migrationDate) {
posthog.reset() // Clears all cached data
}You can configure the featureFlagsRequestTimeoutMs parameter when initializing your PostHog client to set a flag request timeout. This helps prevent your code from being blocked in the case when PostHog’s servers are too slow to respond. By default, this is set at 10 seconds.
React Native
PostHog AI
export const posthog = new PostHog('<ph_project_token>', {
// usually 'https://us.i.posthog.com' or 'https://eu.i.posthog.com'
host: 'https://us.i.posthog.com',
featureFlagsRequestTimeoutMs: 10000 // Time in milliseconds. Default is 10000 (10 seconds).
})When using the PostHog SDK, it’s important to handle potential errors that may occur during feature flag operations. Here’s an example of how to wrap PostHog SDK methods in an error handler:
React Native
PostHog AI
function handleFeatureFlag(client, flagKey, distinctId) {
try {
const isEnabled = client.isFeatureEnabled(flagKey, distinctId);
console.log(`Feature flag '${flagKey}' for user '${distinctId}' is ${isEnabled ? 'enabled' : 'disabled'}`);
return isEnabled;
} catch (error) {
console.error(`Error fetching feature flag '${flagKey}': ${error.message}`);
// Optionally, you can return a default value or throw the error
// return false; // Default to disabled
throw error;
}
}
// Usage example
try {
const flagEnabled = handleFeatureFlag(client, 'new-feature', 'user-123');
if (flagEnabled) {
// Implement new feature logic
} else {
// Implement old feature logic
}
} catch (error) {
// Handle the error at a higher level
console.error('Feature flag check failed, using default behavior');
// Implement fallback logic
}Sometimes, you might want to evaluate feature flags using properties that haven’t been ingested yet, or were set incorrectly earlier. You can do so by setting properties the flag depends on with these calls:
React Native
PostHog AI
posthog.setPersonPropertiesForFlags({'property1': 'value', property2: 'value2'})Note that these are set for the entire session. Successive calls are additive: all properties you set are combined together and sent for flag evaluation.
Whenever you set these properties, we also trigger a reload of feature flags to ensure we have the latest values. You can disable this by passing in the optional parameter for reloading:
React Native
PostHog AI
posthog.setPersonPropertiesForFlags({'property1': 'value', property2: 'value2'}, false)At any point, you can reset these properties by calling resetPersonPropertiesForFlags:
React Native
PostHog AI
posthog.resetPersonPropertiesForFlags()The same holds for group (opens in a new tab) properties:
React Native
PostHog AI
// set properties for a group
posthog.setGroupPropertiesForFlags({'company': {'property1': 'value', property2: 'value2'}})
// reset properties for all groups:
posthog.resetGroupPropertiesForFlags()Note: You don’t need to add the group names here, since these properties are automatically attached to the current group (set via
posthog.group()). When you change the group, these properties are reset.
Automatic overrides
Whenever you call posthog.identify with person properties, we automatically add these properties to flag evaluation calls to help determine the correct flag values. The same is true for when you call posthog.group().
Default overridden properties
By default, we always override some properties based on the user IP address.
The list of properties that this overrides:
This enables any geolocation-based flags to work without manually setting these properties.
Since there is a delay between initializing PostHog and fetching feature flags, feature flags are not always available immediately. This makes them unusable if you want to do something like redirecting a user to a different page based on a feature flag.
To have your feature flags available immediately, you can initialize PostHog with precomputed values until it has had a chance to fetch them. This is called bootstrapping. After the SDK fetches feature flags from PostHog, it will use those flag values instead of bootstrapped ones.
For details on how to implement bootstrapping, see our bootstrapping guide (opens in a new tab).
Since experiments (opens in a new tab) use feature flags, the code for running an experiment is very similar to the feature flags code:
React Native
PostHog AI
// With the useFeatureFlag hook
import { useFeatureFlag } from 'posthog-react-native'
const MyComponent = () => {
const variant = useFeatureFlag('experiment-feature-flag-key')
if (variant === undefined) {
// the response is undefined if the flags are being loaded
return null
}
if (variant == 'variant-name') {
// do something
}
}It’s also possible to run experiments without using feature flags (opens in a new tab).
Group analytics allows you to associate the events for that person’s session with a group (e.g. teams, organizations, etc.). Read the Group Analytics (opens in a new tab) guide for more information.
Note: This is a paid feature and is not available on the open-source or free cloud plan. Learn more on the pricing page (opens in a new tab).
JavaScript
PostHog AI
posthog.group('company', 'company_id_in_your_db')
posthog.capture('upgraded_plan') // this event is associated with company ID `company_id_in_your_db`JavaScript
PostHog AI
posthog.group('company', 'company_id_in_your_db', {
name: 'Awesome Inc.',
employees: 11,
})The name is a special property which is used in the PostHog UI for the name of the group. If you don’t specify a name property, the group ID will be used instead.
To set up error tracking in your project, follow the React Native installation guide (opens in a new tab).
You can use the PostHogErrorBoundary component to capture React rendering errors thrown by components:
React Native
PostHog AI
import { PostHogProvider, PostHogErrorBoundary } from 'posthog-react-native'
import { View, Text } from 'react-native'
const App = () => {
return (
<PostHogProvider apiKey="<ph_project_token>">
<PostHogErrorBoundary
fallback={YourFallbackComponent}
additionalProperties={{ screen: "home" }}
>
<YourApp />
</PostHogErrorBoundary>
</PostHogProvider>
)
}
const YourFallbackComponent = ({ error, componentStack }) => {
return (
<View>
<Text>Something went wrong!</Text>
<Text>{error instanceof Error ? error.message : String(error)}</Text>
</View>
)
}The fallback prop accepts a component to render when an error occurs. The additionalProperties prop lets you add custom properties to the captured error event.
Duplicate errors with console capture
If you have both PostHogErrorBoundary and console capture enabled in your errorTracking config, render errors will be captured twice. This is because React logs all errors to the console by default. To avoid this, set console: [] on errorTracking.autocapture (for example, errorTracking: { autocapture: { console: [] } }) when using PostHogErrorBoundary.
You can use the before_send callback to modify, filter, or suppress exception events before they are sent to PostHog. This is useful for:
React Native
PostHog AI
const posthog = new PostHog('<ph_project_token>', {
host: 'https://us.i.posthog.com',
before_send: (event) => {
if (event.event === '$exception') {
const exceptionList = event.properties?.['$exception_list'] || []
const exception = exceptionList.length > 0 ? exceptionList[0] : null
if (exception) {
// Add custom properties
event.properties['custom_property'] = 'custom_value'
// Override fingerprint for custom grouping
event.properties['$exception_fingerprint'] = 'MyCustomGroup'
}
// Suppress specific exception types
if (exception?.['$exception_type'] === 'IgnoredError') {
return null // Drop the event
}
}
return event
},
})You can also use before_send to sample or filter other event types. See the JavaScript Web SDK documentation (opens in a new tab) for more examples.
To set up session replay (opens in a new tab) in your project, all you need to do is install the React Native SDK and the Session replay plugin, then follow the instructions to enable Session Replay (opens in a new tab) for React Native.
To set up surveys, follow the additional installation instructions for React Native (opens in a new tab). Surveys launched with popover presentation (opens in a new tab) are automatically shown to users matching the display conditions (opens in a new tab) you set up.
Note: URL and CSS selector targeting are not supported in React Native. Surveys that rely on these conditions will not appear.
If you’re not seeing the expected events being captured, the feature flags being evaluated, or the surveys being shown, you can enable debug mode to see what’s happening.
You can enable debug mode by setting the debug option to true in the PostHogProvider options. This will enable verbose logs about the inner workings of the SDK.
React Native
PostHog AI
<PostHogProvider
debug: {true}
apiKey="<ph_project_token>"
options={{
host: "https://us.i.posthog.com",
}}
>You can also call the debug() method in your code.
React Native
PostHog AI
posthog.debug()You may want to disable PostHog when working locally or in a test environment. You can do this by setting the disable option to true when initializing PostHog. Helpfully this allows you to continue using usePostHog and safely calling it without anything actually happening.
React Native
PostHog AI
// App.(js|ts)
import { usePostHog, PostHogProvider } from 'posthog-react-native'
...
export function MyApp() {
return (
<PostHogProvider apiKey="<ph_project_token>" options={{
// Disable PostHog in development (or whatever other logic you choose)
disabled: __DEV__,
}}>
<MyComponent />
</PostHogProvider>
)
}
const MyComponent = () => {
const posthog = usePostHog()
useEffect(() => {
// Safe to call even when disabled!
posthog.capture("mycomponent_loaded", { foo: "bar" })
}, [])
}V1 of this library utilised the underlying posthog-ios and posthog-android SDKs to do most of the work. Since the new version is written entirely in JS, using only Expo supported libraries, there are some changes to the way PostHog is configured as well as actually calling PostHog.
For iOS, the new React Native SDK will attempt to migrate the previously persisted data (such as distinctId and anonymousId) which should result in no unexpected changes to tracked data.
For Android, it is unfortunately not possible for persisted Android data to be loaded which means stored information such as the randomly generated anonymousId or the distinctId set by posthog.identify will not be present. For identified users, the simple workaround is to ensure that identify is called at least once when the app loads. For anonymous users there is unfortunately no straightforward workaround they will show up as new anonymous users in PostHog.
Events such as Application Installed and Application Updated that require previously persisted data were unable to be migrated, the side effect being that you may see much higher numbers for Application Installed events. This is due to the fact that there is no native way of detecting a real “install” and as such, we store a marker the first time the SDK loads and treat that as an install.
JSX
PostHog AI
// DEPRECATED V1 Setup
import PostHog from 'posthog-react-native'
await PostHog.setup('<ph_project_token>', {
// usually 'https://us.i.posthog.com' or 'https://eu.i.posthog.com'
host: 'https://us.i.posthog.com',
captureApplicationLifecycleEvents: false, // Replaced by 'PostHogProvider'
captureDeepLinks: false, // No longer supported
recordScreenViews: false, // Replaced by 'PostHogProvider' supporting @react-navigation/native
flushInterval: 30, // Stays the same
flushAt: 20, // Stays the same
android: {...}, // No longer needed
iOS: {...}, // No longer needed
})
PostHog.capture("foo")
// V2 Setup difference
import PostHog from 'posthog-react-native'
const posthog = await Posthog.initAsync('<ph_project_token>', {
// usually 'https://us.i.posthog.com' or 'https://eu.i.posthog.com'
host: 'https://us.i.posthog.com',
// Add any other options here.
})
// Use created instance rather than the PostHog class
posthog.capture("foo")
// V3 Setup difference
import PostHog from 'posthog-react-native'
const posthog = new PostHog('<ph_project_token>', {
// usually 'https://us.i.posthog.com' or 'https://eu.i.posthog.com'
host: 'https://us.i.posthog.com',
// Add any other options here.
})
// Use created instance rather than the PostHog class
posthog.capture("foo")
// V4 Setup difference
import PostHog from 'posthog-react-native'
const posthog = new PostHog('<ph_project_token>', {
// usually 'https://us.i.posthog.com' or 'https://eu.i.posthog.com'
host: 'https://us.i.posthog.com',
captureAppLifecycleEvents: true, // instead of `captureNativeAppLifecycleEvents` or `autocapture={{ captureLifecycleEvents: true }}`,
// captureMode: 'json', // No longer supported
// maskPhotoLibraryImages: true, // No longer supported
})
posthog.setPersonPropertiesForFlags(...) // instead of `personProperties`
posthog.setGroupPropertiesForFlags(...) // instead of `groupProperties`Ask a question
HelpfulCould be better
This file