Choose how Google uses your shared data

Apps on your device can share data to a personalization index that's stored on your device. Google apps, like Google Search and Assistant, can use this index to give you better recommendations and suggestions. You can choose which app data in the index is used to personalize your experience in Google apps.
 
Even if you don't let Google apps access the data in this index, if you have the Web & App Activity control enabled for your Google Account, Google may still save some app activity data in your account, and personalize your experience based on that data. Learn how to find & control your Web & App Activity.

1. On your device, open Settings.
2. Tap Google  Personalize using shared data.
3. Next to each app or other source, choose whether the data in the index is used for personalization.