1# DataShareExtensionAbility (for System Applications Only) 2 3 4DataShareExtensionAbility provides the data sharing capability. System applications can implement a DataShareExtensionAbility or access an existing DataShareExtensionAbility in the system. Third-party applications can only access an existing DataShareExtensionAbility. For details, see [Cross-Application Data Sharing Overview](../database/share-device-data-across-apps-overview.md). 5