Android/iOS App in Flutter Instrumentation

Overview

This document contains instructions on how to set up OpenTelemetry instrumentation in your Flutter applications and view traces in SigNoz.

Prerequisites

• A Flutter application (Android and/or iOS targets).
• Flutter SDK installed; see the Flutter install guide.
• Access to a SigNoz Cloud account or self-hosted SigNoz instance.

Send traces to SigNoz

Step 1: Install the OpenTelemetry package

flutter pub add opentelemetry

Step 2: Initialize the tracer

Add imports to main.dart:

import 'package:opentelemetry/api.dart';
import 'package:opentelemetry/sdk.dart';

Configure the exporter and tracer provider:

final headers = {
  'signoz-ingestion-key': '<your-ingestion-key>', // Cloud only: paste your ingestion key
};

final exporter = CollectorExporter(
  Uri.parse('ingest.<region>.signoz.cloud:443/v1/traces'), // Cloud endpoint (keep https)
  headers: headers,
);

final processor = BatchSpanProcessor(exporter);
final provider = TracerProviderBase(
  processors: [processor],
  resource: Resource([Attribute.fromString('service.name', '<service_name>')]), // set your service name
);

registerGlobalTracerProvider(provider);

Replace the placeholders:

• <your-ingestion-key>: Your SigNoz ingestion key
• <region>: Your SigNoz Cloud region
• <service_name>: service name that will show up under Traces Explorer in SigNoz.

Step 3: Create spans

final _tracer = provider.getTracer('flutter-example');

void createSpan(String inputText) {
  final rootSpan = _tracer.startSpan('root-span');
  try {
    final childSpan = _tracer.startSpan('child-span', kind: SpanKind.client); // child span example
    try {
      childSpan.setAttribute(Attribute.fromString('input.name', inputText));
      // add your work here
      childSpan.addEvent('Processed input: $inputText');
    } finally {
      childSpan.end();
    }
  } finally {
    rootSpan.end();
  }
}

Step 4: Run the app

Run from Android Studio or an iOS simulator.

Validate

• In SigNoz, go to Traces Explorer and confirm that the traces for your service (for example <service_name>) are present.
• Open a recent trace and verify that spans from your Flutter app are present with the attributes you set.

Troubleshooting

• If spans do not show up, verify the exporter endpoint (Cloud or your self-hosted collector endpoint) and confirm the device/emulator can reach it over the configured protocol (HTTP/HTTPS).

Next steps

• Explore your mobile traces in the Trace Explorer.
• Create latency and error alerts for your service using Alert Management.