[Home](./index.md) > [@snowplow/react-native-tracker](./react-native-tracker.md) > [SessionState](./react-native-tracker.sessionstate.md) ## SessionState interface Current session state that is tracked in events. Signature: ```typescript export interface SessionState ``` ## Properties | Property | Type | Description | | --- | --- | --- | | [eventIndex?](./react-native-tracker.sessionstate.eventindex.md) | number | (Optional) Optional index of the current event in the session | | [firstEventId?](./react-native-tracker.sessionstate.firsteventid.md) | string | (Optional) The optional identifier of the first event for this session | | [firstEventTimestamp?](./react-native-tracker.sessionstate.firsteventtimestamp.md) | string | (Optional) Optional date-time timestamp of when the first event in the session was tracked | | [previousSessionId?](./react-native-tracker.sessionstate.previoussessionid.md) | string | (Optional) The previous session identifier for this user | | [sessionId](./react-native-tracker.sessionstate.sessionid.md) | string | An identifier for the session | | [sessionIndex](./react-native-tracker.sessionstate.sessionindex.md) | number | The index of the current session for this user | | [storageMechanism](./react-native-tracker.sessionstate.storagemechanism.md) | string | The mechanism that the session information has been stored on the device | | [userId](./react-native-tracker.sessionstate.userid.md) | string | An identifier for the user of the session |