---
title: "Sentry's Flutter SDK 10.0: Streaming Traces and More Accurate Crash-Free Rates"
description: "Sentry released Flutter SDK 10.0, making streaming traces the default so spans reach Sentry as they finish, using Sentry.startSpan for custom work. Unhandled Flutter errors no longer mark the session as crashed, improving crash-free rate accuracy by keeping the session running until a real crash occurs. App startup on Android and iOS now has its own trace with breakdowns such as root-widget attachment and first-frame rasterization, and can be extended with SentryFlutter.extendAppStart. The release simplifies logs and metrics setup by removing separate enable flags, expands Dio network error capture to failures without HTTP responses, and respects Flutter’s SensitiveContent widgets in Replay and screenshots. Upgrading requires Dart 3.12, Flutter 3.44, Android API 26, and iOS 15, with native SDK installation via Swift Package Manager on iOS and macOS."
---

# Sentry's Flutter SDK 10.0: Streaming Traces and More Accurate Crash-Free Rates

[Sentry](https://yomu.fyi/company/sentry) · Gino Buenaflor · Oct 14, 2026

**Type:** Announcement

## Summary

Sentry released Flutter SDK 10.0, making streaming traces the default so spans reach Sentry as they finish, using Sentry.startSpan for custom work. Unhandled Flutter errors no longer mark the session as crashed, improving crash-free rate accuracy by keeping the session running until a real crash occurs. App startup on Android and iOS now has its own trace with breakdowns such as root-widget attachment and first-frame rasterization, and can be extended with SentryFlutter.extendAppStart. The release simplifies logs and metrics setup by removing separate enable flags, expands Dio network error capture to failures without HTTP responses, and respects Flutter’s SensitiveContent widgets in Replay and screenshots. Upgrading requires Dart 3.12, Flutter 3.44, Android API 26, and iOS 15, with native SDK installation via Swift Package Manager on iOS and macOS.

## Context

Sentry’s Flutter SDK 10.0 is a major release introducing streaming traces as default and reclassifying unhandled errors to improve crash-free rate accuracy, along with several other improvements and breaking changes.

## Approach / What changed

Streaming traces are enabled by default using Sentry.startSpan for custom work. Unhandled Flutter errors no longer mark the session as crashed; the session continues until a real crash or end. App startup is recorded as a separate trace with breakdowns. Logs and metrics are sent without enable flags but retain filters. Dio capture handles failed requests without HTTP responses. SensitiveContent widgets are masked in Replay and screenshots. Native SDK installation on iOS/macOS now uses Swift Package Manager.

## Takeaways

- Streaming traces are the default in v10: spans are sent in batches as they finish rather than waiting for the entire transaction to end, reducing the time to receive completed span data.
- Unhandled Flutter errors no longer mark the session as crashed in Release Health. The session remains running and is classified as unhandled unless a real crash occurs, making crash-free rates more accurate.
- App startup on Android and iOS now has its own app.start trace with breakdowns like root-widget attachment and first-frame rasterization, and you can extend the measurement for work beyond the first frame using SentryFlutter.extendAppStart.

## FAQ

### How does streaming traces work in Sentry Flutter SDK 10.0?

In v10, the SDK sends spans in batches as they finish, instead of waiting for the entire transaction to end. Custom instrumentation uses Sentry.startSpan which queues the span when the callback completes.

### How do unhandled Flutter errors affect crash-free rate?

They no longer mark the session as crashed. The session stays running and is classified as unhandled unless the app later crashes. This provides a more accurate crash-free rate.

### What are the requirements for upgrading to Sentry Flutter SDK 10.0?

It requires Dart 3.12, Flutter 3.44, Android API 26, iOS 15, and macOS 12. On iOS and macOS, the native SDK is now installed via Swift Package Manager. Profiling has been removed, and native failed-request capture is opt-in.

**Tags:** [Flutter](https://yomu.fyi/topic/flutter), [Mobile](https://yomu.fyi/topic/mobile), [SDK](https://yomu.fyi/topic/sdk), [Sentry](https://yomu.fyi/topic/sentry)

- Source: [Sentry](https://blog.sentry.io/flutter-sdk-10)
- Source URL: https://blog.sentry.io/flutter-sdk-10
- Ingested by Yomu: 2026-10-14T21:00:13.224Z

[Read original post](https://blog.sentry.io/flutter-sdk-10)