Amplitude Experiments Flutter

Flutter SDK for Amplitude Experiment, providing feature flags and A/B testing capabilities.

Features

• Initialize Amplitude Experiments client
• Fetch feature flag variants for users
• Access variants with fallback values
• Manual exposure tracking
• Integration with Amplitude Analytics

Installation

Add this to your pubspec.yaml:

dependencies:
  amplitude_experiments_flutter:
    git:
      url: https://github.com/user/amplitude_experiments_flutter
      path: packages/amplitude_experiments_flutter

Platform Requirements

Platform	Minimum Version
iOS	13.0
Android	API 24

Usage

Initialize

import 'package:amplitude_experiments_flutter/amplitude_experiments_flutter.dart';

// Basic initialization
await AmplitudeExperiments.initialize('YOUR-DEPLOYMENT-KEY');

// With configuration
await AmplitudeExperiments.initialize(
  'YOUR-DEPLOYMENT-KEY',
  config: const ExperimentConfig(
    debug: true,
    fetchOnStart: true,
    automaticExposureTracking: true,
  ),
);

Fetch Variants

// Fetch for a specific user
await AmplitudeExperiments.fetch(
  const ExperimentUser(
    userId: 'user-123',
    deviceId: 'device-456',
    userProperties: {'plan': 'premium'},
  ),
);

// Fetch for anonymous user
await AmplitudeExperiments.fetch();

Get Variant

// Get a variant with fallback
final variant = await AmplitudeExperiments.variant(
  'my-feature-flag',
  const Variant(key: 'control', value: 'off'),
);

// Check variant value
if (variant?.value == 'on') {
  // Show new feature
}

// Check if variant is "on"
if (variant?.isOn == true) {
  // Feature is enabled
}

Get All Variants

final variants = await AmplitudeExperiments.all();

for (final entry in variants.entries) {
  print('${entry.key}: ${entry.value.value}');
}

Track Exposure

// Manual exposure tracking (when automaticExposureTracking is false)
await AmplitudeExperiments.exposure('my-feature-flag');

Clear Cache

// Clear all cached variants (useful on logout)
await AmplitudeExperiments.clear();

Configuration Options

Option	Type	Default	Description
debug	bool	false	Enable debug logging
instanceName	String?	null	Instance name for multiple clients
serverZone	ServerZone	us	Server zone (us or eu)
fetchTimeoutMillis	int	10000	Fetch request timeout in ms
retryFetchOnFailure	bool	true	Retry failed fetch requests
automaticExposureTracking	bool	true	Auto-track exposures on variant access
fetchOnStart	bool	false	Fetch variants on initialization
initialVariants	Map<String, Variant>?	null	Pre-populate variants

Models

ExperimentUser

const user = ExperimentUser(
  userId: 'user-123',
  deviceId: 'device-456',
  userProperties: {'plan': 'premium', 'age': 25},
  groups: {'company': ['Acme Inc']},
);

Variant

final variant = Variant(
  key: 'treatment',
  value: 'on',
  payload: {'color': 'blue'},
);

// Properties
variant.key;      // Variant key
variant.value;    // Variant value
variant.payload;  // Optional JSON payload
variant.isOn;     // true if value is "on"
variant.isOff;    // true if value is null, empty, or "off"

Example

See the example directory for a complete sample app.

License

MIT License - see LICENSE for details.