← Flutter Reference

What is Sentry for Flutter?

Quality · Beginner

By Abdelrahman Saed — Senior Mobile Engineer. Last updated: 2026-08-10.

Sentry is an error tracking and performance monitoring platform that captures unhandled exceptions, native crashes, and performance traces in real time. The Sentry Flutter SDK instruments Dart code, native iOS (Objective-C/Swift), and native Android (Kotlin/Java) layers, giving full-stack crash visibility in production.

How it works

The Sentry Flutter SDK wraps the app's run zone to capture unhandled exceptions:

await SentryFlutter.init(
  (options) {
    options.dsn = 'https://[email protected]/project';
    options.tracesSampleRate = 1.0;  // performance tracing
    options.profilesSampleRate = 1.0; // profiling
  },
  appRunner: () => runApp(MyApp()),
);

Key capabilities:

1. Crash capture — Dart exceptions, Flutter framework errors, native iOS crashes (mach exceptions), and native Android crashes (NDK signals). 2. Stack traces — full Dart stack traces with source maps, even in obfuscated/release builds. 3. Performance tracing — traces slow operations (network calls, screen renders, database queries) with distributed tracing. 4. Session replay — reproduces the exact user interaction that led to a crash. 5. Release tracking — every crash is tagged with the release version, so you know which release introduced it.

At iStoria (5M+ users, 99.9% crash-free), Sentry is the first thing checked every morning. New crashes from the latest release are triaged within hours — before they become store reviews. PII is masked in Sentry events, and cleartext traffic is disabled so crash reports never contain sensitive data.

When to use it

Use Sentry when:

  • You need real-time crash monitoring in production.
  • You want performance tracing alongside crash reports.
  • Your app runs on both iOS and Android and you need unified crash visibility.

Choose Firebase Crashlytics instead when:

  • You're already deep in the Firebase ecosystem and want to avoid another dependency.
  • You need a free tier with no quota concerns.

Strengths

  • Best-in-class Dart stack traces — even in release builds with obfuscation
  • Unified iOS + Android + Dart crash visibility in one platform
  • Performance tracing — see slow network calls, render bottlenecks, and database queries
  • Release tracking — know exactly which release introduced a crash
  • Real-time alerts — get notified within minutes of a new regression

Tradeoffs

  • Pricing scales with events — a 5M+ user app generates a lot of events
  • SDK adds a small runtime overhead — particularly with performance tracing at 100% sample rate
  • Dashboard complexity — the Sentry UI is powerful but not simple

Comparisons

Related case studies

FAQ

Is Sentry better than Firebase Crashlytics?

For Flutter specifically, Sentry has better Dart stack traces and richer performance tracing. Firebase Crashlytics is free, deeply integrated with Firebase, and sufficient for basic crash monitoring. At iStoria, we use Sentry. See our Sentry vs Firebase Crashlytics comparison.

How much does Sentry cost?

Sentry has a free Developer tier (5,000 errors/month). Team and Business plans scale with event volume. For a 5M+ user app, expect to pay for the Business tier. Firebase Crashlytics is completely free, which is its main advantage.

Available for hire. Abdelrahman Saed is a Senior Mobile Engineer (Flutter) — open to full-time, fractional, contract, or advisory work. Hire me →

Book a 20-minute call · Download the CV (PDF) · See how I work