---
title: Update usage from older versions of the React Native SDK
slug: feature-experimentation/docs/migrate-from-older-versions-reactnative-prior-to-v4
docTags: 
createdAt: 2026-08-05T20:40:00.000Z
---

This section provides code examples for how You should leveraging the new [Decision](https://docs.developers.optimizely.com/feature-experimentation/docs/decide-methods-reactnative) and [Event Tracking](docId:-hdTJHUfjXVqVK0gc07Pd) APIs. All existing [Full Stack (Legacy)](docId:6_ik6SSz-WyJLWuCQw7BT) methods and implementation are still supported. See [Optimizely Feature Experimentation - application & migration](docId\:bykQnE4aGRkC5WXhU6Yi5) documentation for the latest updates.

You should adopting the new `Decide`, `Decide All`, and `Track Event` methods as a more flexible and easier-to-use replacement where you currently use `isFeatureEnabled`, `getFeatureVariable`, `getAllFeatures`, or `Track` calls within your implementation.

The following are examples of how to migrate the Full Stack (Legacy) methods to Feature Experimentation methods:

```javascript
// -------------------------------
// Optimizely Feature
// -------------------------------
// old method using Feature component
function MyFeature() {
  return (
    <OptimizelyFeature feature="flag1">
      {(isEnabled, variables) => <Text>{isEnabled} - {variables}</Text>}
    </OptimizelyFeature>
  );
}

// old method using Feature hook
function MyFeature() {
  const [isEnabled, variables] = useFeature('flag1');
  return <Text>{isEnabled} - {variables}</Text>;
}

// new method
function MyFeature() {
  const [decision] = useDecision('flag1');
  return <Text>{decision.enabled} - {decision.variables}</Text>;
}

// -------------------------------
// Optimizely Experiment
// -------------------------------
// old method using Experiment component
function MyExperiment() {
  return (
    <OptimizelyExperiment experiment='experiment1'>
      <OptimizelyVariation variation='firstvariation'>
        <Text>First Variation</Text>
      </OptimizelyVariation>
      <OptimizelyVariation variation='secondvariation'>
        <Text>Second Variation</Text>
      </OptimizelyVariation>
    </OptimizelyExperiment>
  );
}

// old method using Experiment hook
function MyExperiment() {
  const [variation] = useExperiment('experiment1');
  return (
    <>
      {variation === 'firstvariation' && <Text>First Variation</Text>}
      {variation === 'secondvariation' && <Text>Second Variation</Text>}
    </>
  );
}

// new method
function MyExperiment() {
  //decide hook uses flag key. New Api does not support flag-less experiments
  const [decision] = useDecision('flagfor_experiment1');
  return (
    <>
      {decision.variationKey === 'firstvariation' && <Text>First Variation</Text>}
      {decision.variationKey === 'secondvariation' && <Text>Second Variation</Text>}
    </>
  );
}

// -------------------------------
// Track 
// ------------------------------
// unlike other SDKs, no change from old method (optimizely_client.track)
```