Add Sentry Rn

Add Sentry to React Native + Expo

Crash reporting + error tracking + performance monitoring. Evaluate it against the app's privacy, cost, and observability needs.

Privacy, credential, and external action gate

Creating a Sentry project, running its wizard, uploading source maps, or storing an auth token changes external services and may expose app metadata. Obtain owner approval for the Sentry organization/project and data-retention settings first. Never put a DSN, auth token, or source-map credential in this plugin, a public repository, a prompt, or logs.

Why Sentry over alternatives

• Best RN integration (official SDK, source map upload built in)
• Free tier: 5k errors/mo, generous for indie
• Source maps for readable stack traces (vs minified gibberish)
• Replay (see exact UI state at crash)
• Performance traces

Install (Expo)

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npm exec --no -- expo install @sentry/react-native
npx @sentry/wizard@8.0.0 -i reactNative
# Wizard prompts for Sentry org + project, configures everything

This adds:

• @sentry/react-native to deps
• metro.config.js source map config
• iOS native config to ios/Podfile
• Sentry init code to App.tsx or _layout.tsx

Basic init (app/_layout.tsx for Expo Router)

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import * as Sentry from '@sentry/react-native';

Sentry.init({
  dsn: 'https://your-dsn@sentry.io/project',

  // Send errors only in production by default
  enabled: !__DEV__,

  // Performance: 10% sampling for prod
  tracesSampleRate: __DEV__ ? 1.0 : 0.1,

  // Replay: 100% of sessions with errors, 10% otherwise
  replaysOnErrorSampleRate: 1.0,
  replaysSessionSampleRate: 0.1,

  // Track release for source map matching
  release: `com.yourapp@${Constants.expoConfig?.version}`,
  dist: Constants.expoConfig?.ios?.buildNumber,

  integrations: [
    Sentry.mobileReplayIntegration(),
  ],
});

export default Sentry.wrap(RootLayout);

EAS Build integration

Add to eas.json:

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{
  "build": {
    "production": {
      "env": {
        "SENTRY_AUTH_TOKEN": "@sentry-auth-token"
      }
    }
  }
}

After the owner has approved the target project, configure SENTRY_AUTH_TOKEN through an owner-managed EAS or CI secret store. This makes EAS upload source maps on each approved production build; do not store the token in eas.json.

Manual error capture

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try {
  await riskyOperation();
} catch (e) {
  Sentry.captureException(e, {
    tags: { feature: 'paywall' },
    extra: { userId: user.id, action: 'subscribe' },
  });
}

User context (privacy-aware)

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// On login
Sentry.setUser({
  id: user.id, // hashed/anonymized
  // Don't send email or PII unless you have privacy disclosure
});

// On logout
Sentry.setUser(null);

Performance traces (key flows)

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const transaction = Sentry.startTransaction({ name: 'paywall_purchase_flow' });

// ... do work ...

transaction.finish();

Sentry shows P50/P95 timing, breakdowns by step.

Replay (record session leading to error)

Auto-enabled with replaysOnErrorSampleRate. Privacy: by default Sentry masks all text/inputs. To unmask non-sensitive UI:

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<View dataSet={{ sentryUnmask: true }}>
  <Text>This is OK to record</Text>
</View>

Privacy / disclosure

• Add Sentry to your Privacy Manifest (privacy-manifest-rn)
• Mention "we use Sentry for crash reporting" in privacy policy
• Sentry is GDPR-compliant; sign their DPA via dashboard

Common gotchas

• Source maps not uploading? Check SENTRY_AUTH_TOKEN is set in EAS env
• Errors show as "minified.js:1" in production = source map upload failed
• Sentry kills cold start by 50-100ms; use enableTracing: false if perf-critical
• Init MUST be the first thing in your entry file or you'll miss early errors

Pair with

• add-posthog-rn for product analytics (different concern, complementary)
• privacy-manifest-rn to disclose Sentry properly
• versioning-fingerprint so source maps match release versions